The effects of different community fitness centre based exercise referral interventions in overweight and obese adults

ISRCTN ISRCTN13509468
DOI https://doi.org/10.1186/ISRCTN13509468
Secondary identifying numbers ParkwoodTrial
Submission date
20/02/2018
Registration date
06/03/2018
Last edited
18/12/2020
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Other
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Background and study aims
Resistance training is effective at modifying risk factors for metabolic disease. However, there is relatively little research examining community-based resistance training interventions for public health. The aim of this study is to examine the effects of community fitness centre based exercise interventions, delivered through a GP referral scheme, involving resistance training compared with physical activity counselling or a combination of both, upon lean body mass and strength.

Who can participate?
Adults who are overweight or obese, and/or deemed to be at increased risk of type 2 diabetes by their GP, who are not currently taking prescribed medications for any cardiovascular or metabolic conditions

What does the study involve?
Participants enter an exercise referral scheme and are randomly allocated to either a structured exercise program involving resistance training, physical activity counselling, a combination of the two, or a waiting list. Those allocated to the waiting list are randomly allocated to one of the interventions upon completion of the waiting period. At the start of the study and after the interventions (48 weeks) participants have their lean body mass and strength measured.

What are the possible benefits and risks of participating?
Participants benefit from being able to take part in structured exercise interventions or physical activity counselling for 12 weeks, which may result in improvements in lean body mass and strength. The potential risks include injury or other complications as a result of the exercise program.

Where is the study run from?
London Borough of Bexley (UK)

When is the study starting and how long is it expected to run for?
October 2014 to February 2016

Who is funding the study?
Parkwood Leisure and The London Borough of Bexley (UK)

Who is the main contact?
1. Dr Steven Mann (scientific)
2. Dr James Steele (scientific)

Contact information

Dr Steven Mann
Scientific

Waters Edge
Building Nine, Riverside Way
Watchmoor Park
Camberley
GU15 3YL
United Kingdom

Dr James Steele
Scientific

26 28 Bedford Row
London
WC1R 4HE
United Kingdom

Study information

Study designRandomised wait-list controlled trial
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Community
Study typeOther
Participant information sheet Not available in web format, please use the contact details to request a patient information sheet
Scientific titleThe effects of structured exercise, physical activity counselling, or a combination of both, upon strength and body composition in overweight and obese adults taking part in an exercise referral scheme
Study objectivesInterventions including structured exercise will result in greater strength and body composition compared with physical activity counselling, or measurement only control.
Ethics approval(s)National Health Service Research Ethics Committee, London - Queen Square Research Ethics Committee, UK, 01/12/2014, IRAS project ID 172321, REC ref: 15/LO/0540
Health condition(s) or problem(s) studiedPhysical activity and exercise
InterventionThe population (P) was sedentary overweight or obese adults with, or at increased risk of, Type 2 Diabetes. The interventions (I) included three interventions groups described in detail below; a general practitioner (GP) exercise referral scheme of structured exercise (STRUC), physical activity counselling (PAC), or a combination of both (COMB). The comparator (C) was a wait-list control group awaiting entry into the GP exercise referral scheme. Outcomes (O) included body composition and strength.

Participants were randomly assigned to one of four groups including the three intervention groups and one wait-list control group. All interventions were delivered over a period of 12 weeks.

STRUC received one session per week of a structured and supervised GP exercise referral intervention. This intervention was already delivered as part of the care pathway of the local health trust and participants were restricted to these sessions. This programme was based on guidelines published by the American College of Sports Medicine (ACSM). RT loads were based upon calculations of one-repetition maximum (1RM) derived from baseline data (see below). As the studies were conducted in ecologically valid community settings there was some flexibility in the exercises utilised based on participant preferences and any orthopaedic issues/injuries. However, all participants at a minimum followed a full body routine consisting of an upper body multi-joint push (e.g. chest press, overhead press, or dip), upper body multi-joint pull (e.g. pulldown, or seated row), and lower body multi-joint push (e.g. leg press). Exercise professionals met STRUC participants once a month to discuss their progress.

PAC received one session per week of physical activity counselling. The sessions were structured around the model proposed by Haase et al. and no access to fitness facilities.

COMB received a combination of physical activity counselling (sessions in weeks 1, 3, 5, 7, 9 & 11) and a structured and supervised GP exercise referral intervention (sessions in weeks 2, 4, 6, 8, 10 & 12).

The CONT group was formed from a wait-list control facilitated by a legitimate 12-week waiting list for entry into the GP exercise referral intervention. CONT participants received the intervention after this period, though only their waiting list period data was included for analysis.
Intervention typeOther
Primary outcome measureMeasured pre and post (12 weeks) intervention:
1. Body composition, including BF mass (kg), lean mass (kg) and BF percentage (%), measured using bio-impedance (Bodystat 1500, Bodystat, Isle of Man, UK). Guidelines from the National Institute of Health Research Southampton Biomedical Research Centre were followed for body compositions assessment (http://www.uhs.nhs.uk/Media/Southampton-Clinical-Research/Procedures/BRCProcedures/Procedure-for-bioimpedance-with-Bodystat-1500.pdf)
2. Predicted 1RM for chest press, pull down and leg press, obtained by gauging the maximal weight that could be lifted successfully for between 5 and 15 repetitions, and inputting these data into the Brzycki equation (i.e. weight/(1.0278-(0.0278 x No. Repetitions)). These results were collapsed into a single strength measure (the mean of the predicted 1RM for each exercise)
Secondary outcome measuresMeasured pre and post (12 weeks) intervention:
1. Maximal aerobic capacity (VO2max) predicted using the Modified Balke Protocol. Participants walked on a treadmill at between 3.6 and 5.6kph, depending on ability, for 3 min. Following this, the gradient was increased by 1% each minute. Ratings of perceived exertions recorded at 1-min intervals using the OMNI1–10 scale. Oxygen consumption and heart rate continuously monitored via direct gaseous analysis (Fitmate Pro, COSMED, Italy). Predicted VO2max automatically extrapolated using the relationship with heart rate. The test was terminated when participants indicated perceived exertion above six (hard) and/or their heart rate reached 150bpm
2. Mean arterial pressure (MAP), which describes the average arterial pressure during a single cardiac cycle, incorporating both systolic and diastolic phases, but weighted towards the diastolic. Systolic (SBP) and diastolic (DBP) blood pressures (mmHg) were measured using a commercially available blood pressure monitor (Omron Healthcare, Japan). Three readings were collected and the mean value reported. MAP was estimated via the calculation MAP=DBP+0.33(SBP−DBP)
Overall study start date01/10/2014
Completion date01/02/2016

Eligibility

Participant type(s)Patient
Age groupAdult
SexBoth
Target number of participants400
Key inclusion criteria1. Overweight and/or obese (BMI 25-35), and/or at increased risk of type 2 diabetes as determined by their General Practitioner (GP)
2. Not currently taking any prescribed medication for cardiovascular or metabolic conditions
Key exclusion criteria1. Not classified as overweight or obese
2. Not deemed to be at increased risk of Type 2 diabetes as determined by their General Practitioner (GP)
3. Currently taking prescribed medication for cardiovascular or metabolic conditions
Date of first enrolment01/01/2015
Date of final enrolment01/02/2015

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

Crook Log Leisure Centre
Brampton Road
Bexleyheath
DA7 4HH
United Kingdom

Sponsor information

ukactive
Industry

26 28 Bedford Row
London
WC1R 4HE
United Kingdom

Funders

Funder type

Industry

Parkwood Leisure

No information available

London Borough of Bexley

No information available

Results and Publications

Intention to publish date23/05/2018
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryAvailable on request
Publication and dissemination planPlanned publication in BMC Public Health.
IPD sharing planThe datasets generated during and/or analysed during the current study are/will be available upon request from Dr Steven Mann or Dr James Steele.

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article results 27/03/2018 23/11/2020 Yes No
HRA research summary 28/06/2023 No No

Editorial Notes

18/12/2020: Internal review.
23/11/2020: Publication reference added.