Professor Tom Yates and Professor Rob Sayers
Peripheral arterial disease (PAD), caused by a narrowing to the arteries in the lower limbs, is a serious chronic disease that affects around 20% of those over the age of 60 years and dramatically increases the risk of having a heart attack or premature death. Exercise training is a recognised therapy in the treatment of PAD, improving pain free walking distance, physical function and quality of life. However, exercise programmes are not routinely available to patients and have poor uptake or adherence when they are. This PhD programme of research will aim to investigate whether a novel approach to promoting increased physical activity, through breaking prolonged sitting behaviour with short bouts of functional activities, can be used to improve physical function and metabolic health in PAD.
Programme of research
The PhD programme of research will be built around three areas:
1. Defining the prevalence and importance of physical behaviours in PAD
Existing dataset will be used to undertake epidemiological studies describing patterns of physical behaviours (sleep, sedentary behaviours and physical activity) in PAD and how these relate to health markers and outcomes. This will include supporting and utilising data collection from the CODEC cohort of individuals with type 2 diabetes recruited within the East Midlands, as well accessing national datasets such as UK Biobank.
2. Literature Review
A systematic review (and potentially meta-analysis) will be conducted investigating the efficacy of physical activity at improving physical function in PAD. The research question will be designed to address a gap in knowledge, such as the role of light-intensity exercise or adherence and attendance rates within traditional exercise training interventions.
3. Intervention study
An intervention to break prolonged sedentary time improves physical function in those with intermittent claudication
Design: Randomised control trial with assessments at baseline, 6 and 12 weeks
Adults (40-75 years) with intermittent claudication will be recruited from primary and secondary care. Those with dementia, critical limb ischemia, foot ulcers, major amputation, taking insulin therapy or an inability to walk unaided will be excluded.
Individuals will be randomised to standard care control or an intervention to break prolonged sedentary time (B-SED). The B-SED intervention will be designed by the student and aimed at enabling individuals to regularly break sedentary (sitting) time with short bouts of functional activity, including stepping, sit-to-stand repetitions, and arm exercises. The intervention will consist of regular face-to-face and telephone coaching, action planning and self-monitoring.
The primary outcome will be physical function, assessed using the physical performance test (PPT). This test requires participants to complete 9 tasks of daily living, which are scored (0 to 4) based on their ability and speed at carrying out the tasks. Total scores range from 0 to 36. Secondary outcomes will be identified as part of the studentship, but will include: a walking test; objective measures of sleep, sedentary behaviour and physical activity; muscle strength and volume; body composition; markers of cardiometabolic health, depression and anxiety; and quality of life
It is estimated that around 30 individuals will need to be recruited per group (60 in total).
• McCarthy M, Edwardson CL, Davies MJ, Henson J, Rowlands A, King JA, Bodicoat DH, Khunti K, Yates T. Breaking up sedentary time with seated upper body activity can regulate metabolic health in obese high‐risk adults: A randomized crossover trial. Diabetes, Obesity and Metabolism. 2017 Dec;19(12):1732-9.
• Mccarthy M, Edwardson CL, Davies MJ, Henson J, Bodicoat DH, Khunti K, Dunstan DW, King JA, Yates T. Fitness Moderates Glycemic Responses to Sitting and Light Activity Breaks. Medicine & Science in Sports & Exercise. 2017 Nov 1;49(11):2216-22.
• Henson J, Davies MJ, Bodicoat DH, Edwardson CL, Gill JM, Stensel DJ, Tolfrey K, Dunstan DW, Khunti K, Yates T. Breaking up prolonged sitting with standing or walking attenuates the postprandial metabolic response in postmenopausal women: a randomized acute study. Diabetes care. 2016 Jan 1;39(1):130-8.
• Edwardson CL, Yates T, Biddle SJ, Davies MJ, Dunstan DW, Esliger DW, Gray LJ, Jackson B, O’Connell SE, Waheed G, Munir F. Effectiveness of the Stand More AT (SMArT) Work intervention: cluster randomised controlled trial. bmj. 2018 Oct 10;363:k3870.
• Conte MS, Bradbury AW, Kolh P, White JV, Dick F, Fitridge R, Mills JL, Ricco JB, Suresh KR, Murad MH, Aboyans V. Global vascular guidelines on the management of chronic limb-threatening ischemia. European Journal of Vascular and Endovascular Surgery. 2019. S1078-5884(19)30380-6. doi: 10.1016/j.ejvs.2019.05.006. [Epub ahead of print]
• Popplewell MA, Bradbury AW. Why do health systems not fund supervised exercise programmes for intermittent claudication?. European Journal of Vascular and Endovascular Surgery. 2014 Dec 1;48(6):608-10.