An Evaluation of the National Exercise Referral Scheme and its Benefits to

Cardiovascular Health

Henry David Rahman TankBSc Sport & Exercise Science

Abstract

Introduction: In 2002, it was estimated that 16.7million people across the globe die every

year due to CVDs, accounting for 1/3rd of all deaths worldwide (World Health Organisation,

2004). Despite this overwhelming statistic there is still a distinct lack of Cardiac

Rehabilitation (CR) programs that have been implemented and funded. Aims: The aims of

this study were [1] To investigate the levels of participation throughout a moderate

intensity, 16-week exercise regime, and [2] to analyse the health benefits to those who

remain on it. Methodology: This study measured anthropometric data (body mass index,

waist circumference, body mass) and haemodynamic variables (heart rate, systolic blood

pressure, diastolic blood pressure) before and after the physical activity regime. Results: Of

those referred to the scheme by general practitioners, only 53% remained active after 4

weeks and only 36% actually completed it. For those patients that completed the scheme, it

elicited mean reductions to all variables: Body Mass -2.0kg (SD± 20.28), Heart Rate -2.9bpm

(SD± 10.74), Waist Circumference -2.8cm (SD± 14.10), Body Mass Index -0.8 (SD± 6.38),

Systolic Blood Pressure -7.3mmHg (SD± 16.5), Diastolic Blood Pressure -4.9mmHg (SD±

11.33). Statistical Analysis: The data was analyzed using a paired samples t-test, all mean

reductions to parameters were statistically significant (P<0.5). Conclusion: The scheme’s

ability to significantly ameliorate all health parameters greatly evidenced its antipathogenic

and antihypertensive properties; hypothesized earlier in this study, these properties related

to reducing the risk of cardiovascular disease, Type II Diabetes Mellitus, stroke, metabolic

syndrome and even certain cancers (Agarwal, 2009).

Table of Contents

i. Abbreviations........................................................................... 4 ii. Keywords.................................................................................. 5 iii. Acknowledgements............................................................ 5

1.0 Introduction ........................................................................................................................ 61.1 Introduction & Literature Review..……............……...…………..............……............. 6

2.0 Methodology..................................................................................................................... 152.1 Methodology Introduction............................................................................................. 152.2 Ethics....................................................................................................................................... 152.3 Anthropometrics.................................................................................................................152.4 Regime Structure………………………...…...………………………..............…………....... 152.5 Participant Catchment..................................................................................................... 162.6 Experimental Design...............................................…...............................................…… 16

2.6.1 Measures of Adherence............................................... 16 2.6.2 Physiological Parameters........................................... 17

2.7 Statistical Analysis…………………………………….…………................………………..... 17

3.0 Results.................................................................................................................................... 183.1-3.6 Measures of Adherence & Physiological Data.…….....…..….......................... 183.7 Anthropometric and Haemodynamic Data............................................................. .19 3.8 Antihypertensive Properties of the National Exercise Referral Scheme.... 193.9 Obesity Related Hypertension........................................................................................20

4.0 Discussion............................................................................................................................ 214.1 Summary of Results.……………………………………………………………..…………..... 214.2 Pathogenesis of the Metabolic Syndrome and Cardiovascular Disease….. 224.3 Antipathogenic Effects of the National Exercise Referral Scheme…............ 254.4 Scheme Prognostics…………………………..……………………..……………………....... 284.5 The Detrimental Impact of Other Pathologies…………………..…………………..304.6 Conclusion............................................................................................................................ 31 4.7 Limitations & Recommendations............................................................................... 32

References..................................................................................34

i. Abbreviations

AT1 ………..………………………………………………………………………….. Angiotensin Receptors

BMI ………………………………………………………….…………………………………. Body Mass Index

CAD ..……………………………………………………………………………….. Coronary Artery Disease

CR ..……………………………………………………………………………………… Cardiac Rehabilitation

CV ………………………………………………………………………………………………….. Cardiovascular

CVD ……………………………………………………………………………………. Cardiovascular Disease

DBP ………………………………………………………………………………….. Diastolic Blood Pressure

FFA ………………………………………………………………………………………………. Free Fatty Acids

HDL ……………………………………………………………………………….. High Density Lipoproteins

HR ………………………………………………………………………………………………………… Heart Rate

LDL …………………………………………………………………………………… Low Density Lipoprotein

MetS …………………………………………………………………………………….. Metabolic Syndrome

NERS …………………………………………………………………. National Exercise Referral Scheme

RAAS …………………………………………………………. Renin Angiotensin-Aldosterone System

RVLM ………………………………………………………………………. Rostral Ventrolateral Medulla

SBP ……………………………………………………………………………………. Systolic Blood Pressure

SD ……………………………………………………………………………………………. Standard Deviation

SNS …………………………………………………………………………… Sympathetic Nervous System

TG ………………………………………………………………………………………………………. Triglyceride

WC ……………………………………………………………………………………….. Waist Circumference

iia. Keywords

Sympathoexcitation Cardiovascular

Renin-angiotensin aldosterone system Antihypertensive

Rostral Ventrolateral Medulla Obesity

Hypertension Adherence

Adrenergic Haemodynamic

Diabetes Mellitus Epidemiology

Atheromatous Sedentary

Pathogenesis Participation

iib. Acknowledgements

Firstly, I sincerely thank my family and friends who have encouraged and supported

me throughout this degree, also to Cat Lodge who ensured I was consistently focused.

I am eternally grateful to my mother, Kate Brady, who has been the sole driving force

throughout my undergraduate studies and has instilled a work ethic and mental fortitude

that I will indefinitely carry forward into my postgraduate life.

Many thanks also to Daniel Harries, Daniel Thorne, Scott Morris, Phillip Matthews

and Kayleigh Tonge-Jones, all of whom significantly contributed to the inner-workings of

this thesis and greatly facilitated its implementation in Blaenau Gwent.

I am extremely appreciative of the direction and insight that was provided by Pip

Laugharne, whose relentless passion and enthusiasm for the subject has inspired and

guided me throughout all aspects of my degree, in particular that of this research-based

thesis track.

1.0- Introduction & Literature Review

The twenty-first century has seen an unprecedented obesity epidemic; bringing with

it an overabundance of health issues, cardiovascular diseases (CVDs) and concerns with

psychological wellbeing. In 2002, it was estimated that 16.7million people across the globe

die every year due to CVDs, accounting for 1/3rd of all deaths worldwide (World Health

Organisation, 2004). Despite this overwhelming statistic there is still a distinct lack of

Cardiac Rehabilitation (CR) programs that have been implemented and funded.

The approach of all existing CR schemes can vary in many ways; from the exact

conditions they seek to prevent, to the methodology and rationale that they involve.

Regarding protocol differentiation, CR programs can involve methods of future prevention

via the use of direct medication or conversely physical activity based regimes. One such

programme involving the latter is the National Exercise Referral Scheme, funded by the

Welsh Assembly Government. Ranked approximately 8th in the world for deaths per year

from heart disease (World Health Organisation, 2003), it is evident that Wales, like other

communities, must take an active approach to tackle factors leading to death by coronary

heart disease, which alone accounts for approximately 19% of all Welsh mortalities (NHS

Wales, 2010).

The scheme comprises a General Practitioner’s referral for patients with previous or

ongoing cardiac conditions. It involves the completion of a carefully monitored, 16-week

exercise regime, with the objective of introducing long-lasting lifestyle changes as well as

generating physiological improvements. This research project sought to assess and quantify

the level at which the scheme facilitates it’s participants towards cardiovascular recovery,

and in particular that of haemodynamic health.

Optimal adaptation to exercise training requires the development of, and adherence

to, an exercise prescription (Ehrman et al, 2009). It must first be understood that in order

for a patient to fully acquire any improvements to their health, a certain level of adherence

must take place. Effectively, to benefit from physical activity, one must first engage in

physical activity. The two main aims of this study were:

To investigate the levels of participation throughout the regime

To analyse the health benefits to those who remain on it.

A similar evaluation of the scheme conducted in 2010 (Murphy et al, 2010) concluded, “In

sub-group analysis, there were statistically significantly greater effects on all outcomes

among those who completed the 16-week programme”. Assessing 2,160 patients, this study

discovered that the greatest occurrence of withdrawals from the scheme was between entry

to the scheme and the 4 week mark. With only 58% still partaking by this point, a further

14% withdrew over the following 12 weeks. The report administered by the Welsh

Assembly Government focused predominantly on variables pertaining to socio-economic

stability, cost effectiveness and programme reach and adherence; however, even for the

44% that completed the regime, no research was conducted as to whether it actually

benefitted their health.

Upon updating the adherence-based statistics, this study combined them with

analysis of physiological variables in order to accurately assess the scheme’s proficiency in

cardiac rehabilitation. Although no literature is available as yet to support the theorized

physiological benefits of the NERS, there is a wealth of knowledge available to substantiate

its possible importance in our society’s efforts to quash this fast-growing epidemic.

In a meta-analysis report conducted by Agarwal (2012), it stated that, by 2030, the

American Heart Association predict a 9.9% increase in the prevalence of CVDs, a 25%

increase in the prevalence of strokes or heart failures and a consequent rise in the cost of

healthcare to $818 billion. Agarwal’s report stated that, of the 58 million deaths worldwide

in 2005, those caused by cardiovascular diseases equated to almost a third, three times

greater than that of infectious diseases such as malaria, HIV/AIDs and tuberculosis

combined (World Health Organisation, 2004). Given that a vast majority of infectious

diseases are extremely costly and some currently incurable, it is astounding that

supplementation of CR programs is not a worldwide perogative in order to oppose the 25

million CVD-related deaths predicted for 2020.

Be it a maladaptive mind-set likened to geographical inertia, whereby persons

believe the disasters of the world will not affect them, or be it a lack of concrete information

to justify their need to exercise; our global population struggles to see the importance of

minimizing such an ominous yet preventable epidemic which, is not only facilitated by

ignorance, but vastly exacerbated by it.

The known benefits of exercise are far-reaching and simultaneously easy,

inexpensive and effective. Hippocrates (460-377 BC) once stated that “In order to remain

healthy, the entire day should be devoted entirely to ways of increasing one’s strength and

staying healthy, and the best way to do this is through physical exercise”; the timescale of

such an archaic yet innovative finding has certainly waned, but it’s stature and significance

in modern society should not.

Agarwal’s report provides substantial foundation to the notion that regular exercise

has been shown to not only reduce cardiovascular risk factors and chances of morbidity, but

to alleviate the detriment of type 2 diabetes, some cancers, depression, metabolic syndrome,

obesity and falls. Regarding the latter, a new initiative of the NERS seeks to lessen the

occurrence of falls and offset the psychological impairment affiliated with dementia, done so

via the implementation of coordination based, low intensity exercise. This falls prevention

course receives further support from Agarwal’s summaries; stating that range of motion and

stretching exercises reduce sympathetic activity and improve several cardiovascular risk

factor parameters. With the Charity’s proposed expansion follows the need for external

subsidization from philanthropic programs; Agarwal proceeded to suggest that

governmental or corporate funding to employers integrating such regimes can help to

decrease the anticipated burden of CVDs on future populations.

The possible role of the National Exercise Referral Scheme in modern society is

proving more fundamentally important by the year; however, employing a seemingly

minute exercise regime to combat the overwhelming tyranny of cardiovascular disease can,

from an external perspective, appear wholesomely futile. However, recent ecological

approaches to increase participation place the creation of supportive environments on par

with personal skill development and reorientation of health services (King, 1994). The

importance of exercise as a simple method to prevent and counteract CVDs is well known,

so too are the improvements to socio-economic factors and psychological wellbeing induced

by the NERS. Between these two facts lies an area of ambiguity in which, as of yet, there is

no concrete evidence to suggest that government funded exercise regimes have a formative

impact on the cardiovascular health of its participants.

Entitled “An Evaluation of the National Exercise Referral Scheme and its Benefits to

Cardiovascular Health”, this two-pronged research project studied the effectiveness of a

government-funded physical activity regime on reducing cardiovascular risk factors in post

CVD patients; comprising a physiological analysis and adherence-based study.

The aims of the aforementioned scheme are to, over a course of four months,

improve both the mental and physical wellbeing of its patients, as well as to encourage

physical activity for life. Collection and analysis of haemodynamic measures such as blood

pressure (BP) and heart rate (HR) were conducted, enabling an accurate comparison to be

made regarding the patient’s initial cardiovascular fitness and its possible modulations

throughout. According to Mora (et al 2007) such changes in a person’s physiology are both

favourable and more frequent following an increase in physical activity or the initiation of a

structured exercise regime.

Alongside these two variables a further three were measured throughout: body mass,

waist circumference and BMI. Although conceding its limitations, the National Heart, Lung

and Blood Institute (2013) reported that the higher a person’s BMI, the higher their risk of

heart disease, hypertension and certain cancers.

The assessment of weight management aimed to provide conclusion over the

scheme’s possible antihypertensive effects and subsequent improvements to cardiovascular

fitness. Hagberg et al (1990) discovered that during a moderate-intensity exercise regime,

for every two pounds of weight a patient lost there was a 2-mmHG decrease in blood

pressure. Despite uncertainty about their independent effects on mortality, overweight or

obese people are at a greater risk of developing hypertension, diabetes, or having a stroke

(National Institutes of Health Development Panel, 1985). This research project seeks to

further solidify the hypothesis that weight loss, via a structured exercise programme, can

better a patient’s prognosis, paying particular concern to the cardiovascular disease risk

factors.

Concurrent with the conclusions previously formulated by the works of Hagberg (et

al, 1990), research conducted by Judith (et al, 2003) also found evidence of possible

antihypertensive mechanisms that were attributed to weight loss. Additionally, the findings

were similar to that of Agarwal in its cognizance of the CVD epidemic’s projected worsening,

discussing how in Western societies the prevalence of obesity is likely to increase the

burden of hypertension and its consequent cardiovascular mortalities.

Encompassing 25 parallel trials published between 1966 and 2002, this meta-

analysis (Judith et al, 2003) examined correlations between weight loss and blood pressure

reductions, although it did not provide conclusive evidence to the physiology behind it’s

relation, it provided a definitive link between correlative reductions in the two factors and

proposed plausible ideas as to how they intertwined. One such theory being the over-

activation of the renin-angiotensin aldosterone system (RAAS); apparently common in

obese patients (Thethi et al, 2012), this could lead to excessive amounts of the strong

vasoconstrictors Angiotensin II and vasopressin left circulating in the blood stream and thus

expedite hypertension.

A random-effects model was used to account for heterogeneity among trials; an

average weight loss of -5.1kg by means of energy restriction, increased physical activity or

both, reduced blood pressure accordingly. The mean total reduction in systolic blood

pressure (SBP) was -4.44mmHg and -3.74mmHg for diastolic blood pressure (DBP);

expressed per kilogramme of weight loss the reductions in SBP were -1.05mmHg and -

0.92mmHg in DBP.

Reference was made to a similar meta-analysis conducted in 1988 (Staessen et al,

2000), which found that, per kilogramme of weight loss, there was a -2.4mmHg reduction in

SBP, and a -1.5mmHg reduction in DBP. Comprising of thousands of data points, this report

strongly evidenced a correlation between weight loss and reductions in blood pressure,

92% of the studies involved displayed positive modulations to blood pressure in accordance

with weight loss. The Evaluation of the National Exercise Referral Scheme sought to

duplicate the findings of Judith et al (2003) and the other studies prior; these being that

physical exercise indefinitely benefits cardiovascular health, in particular the possible effect

of weight loss on blood pressure.

The role of physical activity in the mediation of cardiovascular disease risk factors is

noticeable across a range of prominent, well-known physiological variables; however,

delving deeper into its effects on the body at a macromolecular level depicts a series of

mechanisms far more intricate than measurements such as weight or arteriovenous blood

pressure. For example, changes to lipid profiles within the human body are often precursors

of the changes to more easily measured physiological variables such as blood pressure, yet

due to the intrusive nature of their measurement techniques the impact of their variations

often goes unnoticed.

Durstine et al (2001) conducted a cross-sectional study to analyse the blood lipid and

lipoprotein adaptations to regular, moderate intensity exercise. The balance of intravenous

lipoproteins can greatly affect a person’s cardiovascular risk factors as well as their

susceptibility to other, similar diseases such as atherosclerosis. Circulating cholesterol and

triglycerides are insoluble in blood and so are encapsulated by lipoproteins; high density

lipoproteins (HDLs), which are smaller in size, consist predominantly of protein and

cholesterol, arguably more beneficial than their larger, lipid-filled counterparts referred to

as low density lipoproteins (LDLs)(Porth, 2011).

HDLs are often referred to as ‘good cholesterol’ most notably due to their

transportation of cholesterol from peripheral, atheromatous plaques to the liver for

excretion. As such, there is an inverse relation between HDL levels and the development of

atherosclerosis (Ridker & Libby, 2008). Conversely, the role of LDLs can be one of detriment

to the human vasculature: endogenous triglycerides (TG) synthesized in the liver are

transported by LDLs to fat and muscle cells, excessive levels of circulating LDLs encourage

their extraction from vessels by scavenging endothelial cells, this is believed to be

associated with the development of atherosclerosis (Guyton & Hall, 2011).

In his analysis, Durstine concluded that exercise eliciting over 1200kcal of

expenditure was associated with 2-8mg/dl increases in HDL levels and reductions in TG

levels of 8-20mg/dl. Additionally, although less commonly reported, reductions in LDL

concentrations also occur as a result of similar exercise regimes, these reductions continue

to be the primary target for cholesterol lowering therapy, particularly in people at risk of

coronary artery disease (CAD) or cardiovascular disease.

These favourable modifications, also prevalent in other studies (Denke & Pasternak,

2001), greatly support the preceding literature and their positive inclination towards

exercise as a preventative method for cardiovascular disease; although such measurements

were unattainable during this NERS evaluation, it was hoped that the implemented exercise

regime would incur similar, desired physiological changes to that of Durstine’s report.

With the general consensus depicting a possible affirmation of the hypothesized

benefits of the NERS, its potential for success provides hope to the cardiovascular health of

future populations.

Regarding the diversity of health benefits achievable via completion of the NERS, the

possible opposition and diminishment of Metabolic Syndrome was attentively hypothesized

in this study. The World Health Organisation defines The Metabolic Syndrome as:

Type II Diabetes, impaired glucose tolerance or normal glucose tolerance with insulin

resistance, together with two or more of the following:

- Abdominal obesity and/or BMI >30kg/m²

- Elevated Blood Pressure (greater than 130/85mmHg or active treatment of

hypertension)

- Low HDL concentrations (< 1.0mg/dl for men, and <1.2mg/dl for women)

- High Triglyceride concentrations (>1.7mmol/L)

- Microalbuminurea (excessive loss of protein in the urine)

Categorized as part of a cascade of conditions and disorders, major adverse

consequences of metabolic syndrome can be the development of cardiovascular disease and

atherosclerosis. Consolidated by its nature and in conjunction with obesity or insulin

resistance, it usually precedes the development of Type II Diabetes (Guyton & Hall, 2011).

Susceptibility to the accruement of metabolic syndrome and consequent diabetes is most

sensitive between the ages of 50 and 60 and thus is referred to as adult-onset diabetes. In

the process of ageing the anatomical and physiological changes to several visceral systems

can lead to functional disability and increased risk of premature death (Harbraouck et al,

1999). Although irreversible on a grander scale, this inevitable senescence is augmented by

physical inactivity and thus can be supplemented with exercise prescription (Ehrman et al,

2009).

The majority of patients enrolled on the National Exercise Regime not only fall into the

approximated age category, but also satisfy the above criteria for Metabolic Syndrome. With

the NERS aiming predominantly to combat obesity and hypertension, its subsequent success

would theoretically eliminate two of the five criteria pertaining to metabolic syndrome. The

results obtained by Judith (et al, 2001) and Staessen (et al, 2000) suggested a strong

possibility of this occurrence. Furthermore, the reported, favourable changes to lipid

profiles as a result of exercise (Durstine et al, 2001) substantiated the possibility of reduced

triglyceride concentrations and increased HDL concentrations as consequence to regular,

moderate intensity exercise. Further epidemiological evidence also supports the role of

exercise in the primary prevention or delay of Type II Diabetes (Xiao et al, 1997).

Adopting a theoretical perspective, metabolic syndrome can be regarded as an operative

template for the transition between the accumulation of smaller, less aggressive disorders,

and the development of more severe conditions, diseases or risk factor parameters.

The National Exercise Referral Scheme aims to facilitate cardiovascular health

replenishment and seeks to lessen risk factors associated with the development of

cardiovascular disease. Application of the above transitional model supports the hypothesis

that regular, moderate intensity exercise can induce an abundance of health benefits related

to the aforementioned conditions. Considered as method of CVD and MS prevention, this

study aims to further elucidate the scheme’s ability to reduce their associated risk factors,

and consequent contraction of type II diabetes and cardiovascular disease; the findings of

Judith (et al, 2001) and Durstine (et al, 2001) support the theorized combatting of metabolic

syndrome and CVD prerequisites such as obesity, hypertension, low LDL concentrations and

high TG levels.

If left to accumulate however, these parameters are considered to conjunctively

represent metabolic syndrome, if untended to there is a possibility for worsening of health

in the development of diabetes or cardiovascular disease. The previously stated benefits of

exercise concluded by Agarwal (2012) lend suggestion to the possible treatment of MS

through exercise and a reduced risk of CVD as consequence; stating that regular exercise can

not only reduce CVD-risk factors but accordingly alleviate the detriment of type II diabetes

and metabolic syndrome.

There is a dearth of information available that is applicable to this physiological theory,

supporting the hypothesis that exercise can reduce such risk factors in the early stages of

this chronological pathway, or conversely combat their developments in the later stages

once accrued. The findings exhibited in the preceding literature aid aims and aspirations of

this study in its attempt to solidify the benefits of the NERS across a range of health

variables and risk factor parameters. This study sought to definitively conclude that the

implementation of a monitored, 16-week exercise regime can: reduce CVD and MS risk

factors, actively counter metabolic syndrome, and finally lessen the detriment of a plethora

of subsequent conditions such as cardiovascular disease, diabetes and atherosclerosis. Thus,

the following working hypotheses were postulated:

H1 = Participation levels would decrease throughout the scheme and it would elicit

favourable reductions to all health parameters.

H0 = Participation levels would remain constant throughout the scheme and it would

elicit unfavourable increases to all health parameters

2.0 - Methodology

2.1 - Methodology Introduction

This section of the study denotes the methods, protocols and equipment used during its

research and data collection components, and subsequently that of the statistical analysis

conducted upon said data. This two-pronged research project investigated both the levels of

adherence on the National Exercise Referral Scheme and the physiological benefits attained

by those who completed it.

2.2 - Ethical Issues

Prior to research, all patients completed a series of forms to assess their eligibility and

safety to proceed, such as a Physical Activity Readiness Questionnaire and an EQ-5D

Questionnaire (see Appendices). Additionally a Participant Information Sheet was issued in

order to fully explain the safety precautions, protocols and rationale of the study. A HESAS

Ethics Undergraduate Research Form was approved and signed by a member of the Faculty

of Life Sciences and Education Undergraduate Research Committee to verify that the study

was ethically appropriate.

2.3 - Anthropometrics

During an initial consultation various anthropometric measures were recorded, all

measurements were conducted three times and an average attained for each: Height (cm),

Weight (kg), Waist Circumference and also BMI using the following equation:

BMI=Weight (kg)Height ² (m )

2.4 - Regime Structure

Following referral of patients and completion of an Initial Consultation an exercise schedule

was implemented; participants were to complete 2 hours of moderate intensity exercise

each week consisting of two 60-minute exercise classes. This involved choice of either a

Gentle Exercise Class or a Gym-based Exercise class. Participants are lead by a NERS

exercise Coordinator through various warm-up and stretching movements before

commencing the above circuits. All movements are of low to moderate intensity and are

attentively monitored by the exercise professional throughout. Following the circuits a

gentle warm-down session is conducted.

2.5 - Participant Catchment

40 elderly, ambulatory men and women (aged 50-85 years) with a mean body weight of

96kg (SD± 20.28) were recruited for this study. All were at risk of, or had a medical history

involving cardiovascular disease, diabetes, strokes, certain cancers or general concerns

surrounding obesity (see NERS Inclusion Criteria in Appendix). A General Practitioner

referred all participants in this study to the NERS.

2.6.1 Experimental Design - Measures of Adherence

This section of the study investigated the number of participants who remained on the

NERS at each of its consultatory stages: Initial Referral, First Consultation, Introductory

Session, Consultations at weeks 4, 8, 12 and 16 upon scheme completion followed by a 12

Month Lifestyle Meeting. It assessed the figures of those initially referred that completed the

scheme and those who did not.

2.6.2 - Experimental Design: Physiological Measures

The measurement of physiological variables constituted the main analytical hub of this

study; during each consultatory stage six health parameters were measured three times and

an average attained. Systolic and diastolic blood pressure (mmHg) were measured using an

automatic blood pressure monitor (OMRON M3 HEM-CR24, Healthcare Co, Ltd, Kyoto,

Japan, made in Vietnam: P Intelli Sense) two cuff sizes were used: Standard Adult Cuff (22-

32cm) and a Large Adult Cuff (32-42cm). Body Mass (kg) and BMI were measured using

Marsden electronic scales (Model MPPS-250 by Marsden/The Weighing Company: Made in

China by Charder Electronic Co, Ltd). Height (cm) was measured using Seca Measurement

Systems and Waist Circumference was measured using a standard orlistat (Manufactured by

Xenical), done so midway between the uppermost boarder of the iliac crest and the lower

boarder of the costal margin. For overweight or obese patients whose skeletal landmarks

were not easily located, the tape was aligned with the patient’s belly button.

2.7 - Statistical Analysis

Upon satisfying the assumptions of normality and homogeneity of variance, a paired

samples t-test was conducted using SPSS Statistics v.22 (IBM, Armonk, NY, USA). Results

were compared before and after scheme completion to determine whether any changes

were statistically significant.

3.0 – Results3.1-3.6 - Measures of Adherence & Physiological DataThe figures below (figure 3.1 – 3.6) depict the changes to each variable before and after scheme completion with relation to the participation levels during each consultatory stage.

3.7 – Anthropometric & Haemodynamic Data

3.8 - Antihypertensive Properties of NERSFigure 3.8 was formulated to highlight the prevalence of favourable blood pressure reductions. It depicts the percentage of patients who experienced favourable changes to all, some or none of the variables; also illustrated is the percentage of patients whose unfavourable changes were attributed to blood pressure.

3.9 Obesity-Related Hypertension To further elucidate the possible interaction between obesity and hypertension in the metabolic syndrome, figure 3.7 (below) was devised to depict the relationship between the Systolic Blood Pressure and Body Weight values of NERS patients. This interaction, as discussed by Judith (et al, 2003), is prevalent in the metabolic syndrome and plausibly revolves around over -activation of the renin-angiotensin aldosterone system and sympathoexcitation.

4.0 - Discussion

4.1- Summary of Results

The findings of this study have further elucidated the possible benefits to health

achieved via the implementation of an exercise regime; all reductions to variables were

statistically significant and the scheme’s ability to restore its patients’ health was evidenced

substantially, with particular reinforcement made to it’s previously theorized

antihypertensive properties. These findings conclusively satisfied the following working

hypothesis:

H1 = Participation levels would decrease throughout the scheme and it would

elicit favourable reductions to all health parameters.

The analytical perspectives of this two-pronged study focused firstly upon the

evaluation of adherence throughout the scheme and secondly upon the benefits to health

achieved by those who remained on it. The adherence-based statistics showed that, of those

referred to the scheme by general practitioners, only 53% remained active after 4 weeks

and only 36% actually completed it. Although drastic reductions in participation were

exhibited, analysis of physiological and anthropometric data showed that, for the 36% who

completed the scheme, the following modulations to health were incurred:

1. Body weight: –2.0kg (SD± 20.28 / P = 0.00109†)

2. Waist Circumference: -2.8cm (SD± 14.10 / P= 0.00008†)

3. Heart Rate: -2.9bpm (SD± 10.74 / P= 0.01399†)

4. Body Mass Index: -0.8 (SD± 6.38/ P= P= 0.00185†)

5. Systolic Blood Pressure: -7.3mmHg (SD± 16.5 / P= 0.00003†)

6. Diastolic Blood pressure: -4.9mmHg (SD± 11.33 / P= 0.0008†)

4.2 - Pathogenesis of Metabolic Syndrome and Cardiovascular Disease

The pathogenesis of metabolic syndrome, cardiovascular disease, and type II

diabetes mellitus encompasses a vast network of elaborate physiological inter-

relationships; these highly integrated mechanisms, which are concomitant with positive

energy balance and a sedentary lifestyle, are not only inter-dependent but are often up-

regulatory of one another (Kishi & Hirooka, 2013).

The purpose of using simple anthropometry in the identification of those at

increased health risk is to identify those with CVD risk factors (Janssen et al, 2004). In

addition to anthropometrics, the other variables measured in this study focused

predominantly on internal physiological changes to provide a broader yet more meticulous

insight as to the changes to health that occurred. Although not definitive predictors of

cardiovascular risk, all epidemiological studies that sought to answer questions about BMI,

heart rate and all-cause morbidity, reported that increases to either are greatly associated

with a higher risk of all-cause morbidity and CV events (Perret-Guillame, 2009).

The metabolic syndrome is predominantly characterized by impaired glucose

tolerance, elevated blood pressure and visceral obesity; patients who satisfy these criteria

are three times more susceptible to cardiovascular-related death than healthier

counterparts; as such metabolic syndrome is rapidly becoming a global concern (Kishi &

Hirooka, 2013).

The schema overleaf (figure 4.2.1) was devised to depict the pathogenesis of more

severe conditions through the accruement of earlier risk factor parameters such as

hypertension and abdominal obesity. As previously discussed, depending on the type and

severity of worsening to these parameters, they can be collectively known as metabolic

syndrome.

It must first be understood that the processes depicted in the schema are more often

accumulative as a result of poor diet or lack of exercise; as changes to certain measures

amass, so too does the risk of developing cardiovascular disease or other conditions.

Figure 4.2.1 depicts the process of health degeneration across a temporal baseline from normal health to the development of cardiovascular disease and other pathological conditions

Figure 4.2.1 – Schema to depict the pathogenesis of cardiovascular disease. Ref; 1: Kishi & Hirooka, 2013. 2: Canale et al, 2013. 3: Janssen et al,

2004. 4: Perret-Guillame et al, 2009. 5: National Heart, Lung and Blood Institute, 2013. 6: National Institute of Health Development Panel,

1985. 7: Guyton & Hall, 2010. 8: Ford, 2005.

With regards to the schema, those classified as obese, hypertensive or somewhat diabetic

exhibit a rightward shift toward metabolic syndrome (Stage 1). Concordant with a

continued absence of lifestyle modifications or nutritional interventions is a possible,

further shift toward cardiovascular disease through the damaging accumulation of later risk

factor parameters (Stage 2). Consequential perseverance of these aggressive comorbidities

can, if unopposed, ultimately lead to the contraction of cardiovascular disease, type II

diabetes mellitus, atherosclerosis and even certain cancers (Poirier et al, 2006).

The underpinning physiological concepts to which these quantifiable, pathogenic

changes are attributed, pertain predominantly to the over-activation of the sympathetic

nervous system (SNS) (Kishi & Hirooka, 2013). Thermogenesis and blood pressure are both

under adrenergic control (Canale et al, 2013), thus in the pathogenesis of hypertension,

metabolic syndrome, and CVD, underlying SNS activation is critically involved; additionally,

previous studies have suggested that this activation is notably interactive with insulin

resistance and stimulation of the renin-angiotensin aldosterone system (RAAS) (Grassi et al,

1981). In accordance to hypertension, central obesity demonstrates augmented sympathetic

outflow when compared to non-central adiposity even in the absence of elevated blood

pressure, which, if also present, further augments the sympathetic nervous system (Kishi &

Hirooka, 2013).

A schema formulated by Kishi & Hirooka (2013) illustrated the pathogenesis of

hypertension and subsequent obesity in the metabolic syndrome; although conceptual it

depicted the mechanisms plausibly involved. Over-activation of the RAAS, which frequently

occurs in obesity (Thethi et al, 2012), can result in heightened levels of the vasoconstrictor

angiotensin II left circulating in the blood stream; as such the pathogenesis of obesity-

related hypertension in the metabolic syndrome is considered to be substantially involved

in the development of cardiovascular disease.

Sympathoexcitation associated with the renin-angiotensin aldosterone system in MS

elicits a considerable degree of oxidative stress on the rostral ventrolateral medulla (RVLM)

and thus is considered neurogenic. This stress, induced by the coupling of angiotension-1

receptors (AT1) and their ligand angiotensin II, markedly potentiates sympathetic neural

discharge; resultantly this increases intravenous insulin levels and elevates blood pressure

accordingly. Moreover, RAAS-induced secretion of renin increases water and electrolyte

retention in the kidneys; osmotic distension of interstitial fluid and surrounding cells

constricts the intrarenal vasculature and increases blood pressure (Guyton & Hall, 2011).

SNS activation is partly aimed at -adrenergic thermogenesis to promote negativeβ

energy balance, decreased fat storage and weight loss, however; its normal activation of

brown adipose tissue and other baseline mechanisms do not occur in obese patients (Kishi

& Hirooka, 2013). Additionally, its subsequent activation of the RAAS is of considerable

detriment to intra-physiological mechanisms, expediting lipolytic production of non-

esterified free fatty acids (FFAs) and increasing insulin resistance.

4.2- Antipathogenic Effects of the National Exercise Referral Scheme

It is ubiquitously known that regular exercise benefits health, but with regard to the

alleviation of CV-risk factor parameters during the later stages of pathogenesis, the exact

exercise intensity that yields the greatest benefit is relatively unknown (Tjønna, 2007). The

National Exercise Referral Scheme aims to regenerate the health of its patients or

significantly ameliorate a multiplicity of risk factor parameters. The hopes and aims of this

study were to quantitatively evidence the scheme’s capacity to reduce the risk of

cardiovascular disease, theoretically eliminate the metabolic syndrome or even guide it’s

patients back to normal health.

Applying the findings of this study to the previously devised theoretical schema (figure 4.3.1) enabled its orientation to be modified in favour of the antipathogenic effects of the National Exercise Referral Scheme. Figure 5.1 depicts the pathogenic pathway of cardiovascular disease and it’s subsequent reversal following the implementation of an exercise programme

Figure 4.3.1 – Antipathogenic effects of the National Exercise Referral Scheme. Ref; 1: Agarwal, 2012. 2: Tjønna, 2007. 3: Perret-Guillame,

2009. 4: Janssen et al, 2004. 5: Esler et al, 2006. 6: Judith et al, 2003. 7: Durstine et al, 2001. 8: Denke & Pasternak, 2001. 9: Xiao et al, 1997.

Typographical Dagger denotes statistical significance.

Figure 4.3.1 depicts the possible antipathogenic effects of regular, moderate intensity

exercise with regards to cardiovascular disease, type II diabetes mellitus, atherosclerosis,

metabolic syndrome and even certain cancers (Agarwal, 2012). Although comprised

primarily of the data collected in this NERS evaluation, supplementary information is

exhibited where other, comparable studies have elicited applicably similar or additional

modulations to these health parameters.

The physiological interconnectedness of these parameters, as discussed, appears to

principally revolve around sympathoexcitation, adrenergic overdrive and over-activation of

the renin-angiotensin aldosterone system; previous studies have stated that moderate

intensity exercise incorporating stretching and range of motion movement patterns can

reduce sympathetic activity and improve several other CVD risk factors (Agarwal, 2012).

This knowledge, compiled with that of the Gentle Exercise Class’ steady, mobility-based

approach (see Methodology), provides ample explanation to the positive modulations

incurred by this scheme.

As a central feature contributing to the mortality and morbidity associated with metabolic

syndrome (Canale et al, 2013), weight management was monitored attentively throughout

the scheme. The mean reductions to weight (-2.0kg ± 20.28) were of favourable orientation

and, with several patients shedding an excess of 10kg and one even 16.2kg, were not

conclusively demonstrative of the scheme’s potential. Plausibly interactive with obesity,

alterations to blood pressure scores were equally scrutinized.

Regular exercise reduces blood pressure, its sympathetic inhibition, preferentially

involving that of renal sympathetic outflow, is well placed to achieve an antihypertensive

effect (Esler et al, 2006). The scheme incurred a significant mean SBP decrease of 7.3mmHg

(±16.5), and mean DBP decrease of 4.9mmHg (±11.33). In addition to the mean values, 40%

of patients who were initially considered to be hypertensive reduced either DBP or SBP to

normotensive thresholds; furthermore 8% of patients reduced both DBP and SBP to

normotensive values. An increase in blood pressure of 10mmHg is associated with a 20%

increase in the risk of cardiovascular-related death (Perret-Guillame, 2009); consequently,

for the 43% of participants who exhibited a 10mmHg SBP reduction, their risk of CV-related

death was reduced by one fifth.

Of the three variables measured in this study pertaining to the metabolic syndrome,

waist circumference also exhibited significantly favourable modulations in addition to the

variables prior. It has been established that abdominal obesity, assessed by waist

circumference, effectively predicts obesity-related health risk (World Health Organization,

1998); thus favourable reductions in the former would subsequently lessen the detriment of

the latter. Mean reductions to waist circumference of 2.9cm (±14.1) were exhibited

following completion of the scheme; 77.5% of the population reduced their WC with three

patients showing reductions of 10cm or more and one eliciting an 18cm decrease. Of the

22.5% who did not reduce their WC, only two patients showed increases of a greater margin

than that of the group’s mean reduction.

The metabolic syndrome encompasses a constellation of risk factors, two of which

being abdominal obesity and hypertension; however, due to the invasive techniques

required to assess the remaining criteria, the metabolic syndrome could not be accurately

diagnosed within this study. Conversely, of the 88% who originally satisfied one criterion or

more, analysis was conducted as to whether these fulfillments remained, or if reductions to

these prerequisites below MS baselines occurred. Of this population, 49% experienced

positive changes to one or more of the parameters associated with MetS, subsequently

reducing their risk of metabolic syndrome and cardiovascular disease (Agarwal, 2012).

In accordance with these changes, it is hoped that the remaining criteria and their

underpinning intra-physiological mechanisms underwent antipathogenic alterations.

Previous studies have detailed that in addition to reducing BP and WC, exercise, particularly

regimes of longevity, can elicit significant reductions to triglyceride concentrations

(Durstine et al, 2002), increase HDL concentrations, abolish microalbuminurea and thus

partly or fully reverse the metabolic syndrome (Tjønna, 2007). Conclusively it is hoped that,

although currently immeasurable under NERS data collection protocol, such desired

physiological changes also befell the patients of the National Exercise Referral Scheme.

The metabolic syndrome does not incorporate changes associated with body mass

index or heart rate, however they are widely acknowledged as independent risk factors for

cardiovascular disease and other pathological conditions (Janssen et al, 2004. Perret-

Guillame, 2009).

Interventions designed to reduce BMI would likely obtain maximal benefits in

reducing the incidence or prevalence of CVD risk factors (Janssen et al, 2004).

Implementation of the NERS’ exercise regime reduced the population’s mean BMI scores by

0.8kg/m2 (±6.38). With knowledge of its association to all-cause cardiovascular morbidity,

these reductions to body mass index and their subsequent implications were considered to

be in some way anti-pathogenic.

Due to the risks associated with an accelerated heart rate being not only statistically

significant, but also clinically relevant (Perret-Guillame, 2009), patient’s heart rates were

carefully monitored throughout this analytical study. Regarding the study population, the

implemented exercise regime induced a mean heart rate reduction of 2.9bpm (±6.38).

Moreover, 18% of participants exhibited a heart rate reduction of 10bpm or more, which,

congruent with a 10mmHg blood pressure decrease, is associated with lessening the risk of

cardiovascular-related death by 20% (Perret-Guillame, 2009).

4.4 - Scheme Prognostics

The south wales valleys suffer from a number of socio economic problems (David et

al, 2003), when juxtaposed with the expeditious increase in CVD mortalities it is evident

that an influx of health and lifestyle interventions must be deliberated and endorsed.

Further fortification of such schemes could likely impose a multitude of benefits across not

only health and wellbeing platforms but also those of socio economic orientation.

Regular physical activity substantially aids mood improvement, personal capacity for

work and recreation, and also enhances motivational climate (Ntoumanis et al, 1999). The

socially inclusive approach of this exercise scheme bares testament to the breadth and

variety of benefits than can be achieved by partaking; providing a medium in which

community adhesion can grow and prosper, the opportunities it provides to socially interact

with like-minded individuals could, although not necessarily quantifiable, provide hope to

these at-risk societies.

The influence of these interactive environments can also alleviate the detriment of

neurological and psychological conditions such as anxiety and depression which, upon

assessment of other, similar exercise referral schemes, have proved to be significantly

reduced via the implementation of a physical activity regime (Pavey, 2011. Murphy et al,

2010). Additionally, when compared to anti-depressant pharmaceuticals, the

implementation of a 16-week exercise regime has proved equally as effective at reducing

depression levels (Blumenthal et al, 1999). Also evidencing positive modulations to

haemodynamic variables, many of these other exercise referral based studies have stated

that, if maintained over time, adherence to these physical activity regimes could bring about

population-level benefits in health.

The current literature available to substantiate the benefits of exercise is indeed

diverse and plethoric; for example, those with good muscoskeletal flexibility, which is highly

attainable through physical activity, will significantly reduce the risk of lower back injury

(Cady et al, 1979). This beneficial adaptation however can extend beyond the confines of

chiropractics and also positively transcend into day-to-day life, such as substantially

improving safety whilst driving (West Virginia University, 1988).

Summating the antipathogenic findings of this study with the neuropsychological

(Pavey, T. 2011. Murphy et al, 2010. Blumenthal et al, 1999), cardiovascular (Agarwal

2010), and economic (Agarwal, 2010) benefits evidenced in similar exercise schemes,

provides substantial support to the hypothesised future impact of exercise referral schemes

across a range of parameters. In addition, other reported improvements to muscoskeletal

mechanisms (Cady et al, 1979), oncological concerns (Sternfeld, 1992) and respiratory

pathologies (Ries et al, 1995), bare testament to the heterogeneity of potential

improvements to health incurred by regular, moderate intensity exercise.

4.5 - The Detrimental Impact of Other Pathologies

In 2005 there were 58 million deaths worldwide, those attributed to cardiovascular

disease equated to almost a third (World Health Organization, 2004). As the most common

cause of death from cancer, lung cancer claimed the lives of 1.18 million people out of 1.35

million initially diagnosed in 2005 (American Cancer Society, 2005). Equally as fatal,

Leukemia claimed 222,000 lives of the 300,000 diagnosed in 2005; this poor patient

prognosis is partly attributed to the complex and often unattainable treatment

administrations that are required. Although having a large bearing on global deaths, cancer,

even when combined with deaths attributed to all infectious diseases, did not equal that of

cardiovascular morbidities.

The ratio of malaria diagnoses and subsequent mortalities is substantially lower

than that of its cancerous counterparts, yet each year Malaria claims the lives of

approximately 584,000 people of 198 million who are diagnosed. Once again a vast majority

of these deaths are attributed to the inaccessibility of costly health interventions such as

insecticide-treated mosquito nets or artemisinin-based therapies (World Health

Organization, 2004).

Emerging from this statistical juxtaposition is a distinct and concerning trend; it

revolves principally around the inaccessibility of certain medical interventions and thus the

limited ability to mitigate the detriment of various pathologies. With knowledge that

cardiovascular disease accounts for 1/3 of global deaths each year, it is staggering that the

well known, far-reaching and simultaneously easy, inexpensive and effective (Agarwal,

2012) methods of prevention such as exercise are not given the respect or funding that they

require and as consequence 16.7 million lives are claimed by it each year.

4.6 - Conclusion

The National Exercise Referral Scheme, as quantitatively and qualitatively evidenced

in this study, is definitively beneficial to the health and wellbeing of its patients. The

implemented exercise regime elicited favourable reductions to diastolic and systolic blood

pressure, body weight, body mass index, heart rate and waist circumference. The scheme’s

ability to ameliorate these health parameters greatly evidenced its antipathogenic and

antihypertensive properties; hypothesized earlier in this study, these properties related to

reducing the risk of cardiovascular disease, Type II Diabetes Mellitus, stroke, metabolic

syndrome and even certain cancers (Agarwal, 2009).

The findings of this study have definitively elucidated the National Exercise Referral

Scheme’s ability to reduce the risk of the metabolic syndrome and cardiovascular disease. In

addition, the scheme elicited favourable reductions to all parameters, and due to the

reduction of CVD risk, reduced accordingly was the risk of developing atherosclerosis and

subsequent injurious consequences to visceral systems throughout the body (Guyton & Hall,

2011). The ill-omened tyranny of cardiovascular disease currently claims more lives each

year than any other disease, pathological condition, accident, war or natural disaster (World

Health Organisation, 2004); however, increasing knowledge of its effective preventative

methods equips today’s societies with a dexterous arsenal of techniques and practices that

can aid overcoming it, now added to this arsenal are the recently affirmed and scientifically

proven benefits of the National Exercise Referral Scheme.

4.7 - Limitations & Recommendations

Although proving conclusively beneficial to its participants, this study conceded

various limitations and measures that, if counteracted in a future study, could further

substantiate the data set and authenticate the antipathogenic conclusions.

Firstly, in comparison to the vast volume of patients that the National Exercise

Referral Scheme treats the data set examined was relatively deficient. The time frame within

which the study was conducted ran parallel to two terms during a University academic year;

increasing the study’s longevity would proportionately heighten the quantity of current or

new patients that could eligibly partake. Moreover, increased frequency of data collection

would present much more information to be included in means, trends and graphical

representations. As such, the study’s elicited conclusions would provide a more meticulous

insight into the health benefits achievable by the NERS regime and represent them more

reliably.

Similar to an increased data set, the addition of further variables and measures might

also strengthen the findings; to give example, incorporating an exercising heart rate via the

implementation of HR monitors would more effectively elucidate the hearts capability and

functionality within an active, exercising medium. Furthermore, depending on ethical issues

or accessibility of equipment, the utilization of blood sampling could provide insight into the

modulations to lipid profiles throughout the regime; similar to Agarwal’s (2012) findings it

could proficiently assess a patient’s susceptibility to conditions such as atherosclerosis.

The NERS database management protocols, although effective, were considered a

partial limitation. Although a separate database was created for the duration of this study,

the implementation of new NERS modes and protocols could expedite the processes of data

collection, storage and retrieval - subsequently enhancing the efficiency and confidentiality

of data storage at the National Exercise Referral Scheme.

As highlighted in this study, one key limitation of the exercise regime was the patient

adherence and participation levels throughout the scheme with only 53% of the population

still active by week 4. Upon discussion with the patients involved, it became definitively

apparent that the limitations to participation significantly focused upon transport and

accessibility, which, to those with disability or impairment, often revolves around the

goodwill and availability of family and friends (Oliver et al, 1988). To ameliorate current

outreach and accessibility strategies within the scheme could perhaps breadthen the

scheme’s catchment and increase the volume of patients journeying from initial consultation

through to completion.

However, the plausible methods of which to increase the prevalence and success of this

scheme would likely have a significant financial impact on this charitable organization.

Furthermore, due to the current economic decline of rural Welsh areas (David et al), the

required injection of capital to these rehabilitative schemes is not one that is necessarily

feasible.

In conclusion, the limitations of this study involved the implementation of further

measures in which to strengthen the orientation and depth of the current findings.

Regarding those limitations pertaining to the National Exercise Referral Scheme itself, they

appear to revolve predominantly around financial, societal and socio-economic issues as

opposed to the actual rehabilitative protocols currently in place that have proved

substantially beneficial to the health of it’s patients.

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