This is a plain English summary of an original research article
Pedometers and accelerometers helped people with diabetes or cardiovascular diseases to increase their physical activity by a moderate amount, though pedometers were more successful. Programmes that involved face-to-face consultations with a facilitator were more effective than those where devices were used in isolation to track progress.
This NIHR-funded systematic review included 36 trials which objectively measured the activity of people with cardiac or metabolic conditions, and in which wearable technology was part of the intervention. Most studies were relatively short-term, with a mean follow-up of 32 weeks. People wearing pedometers walked on average an additional 1,703 steps daily, compared with people not wearing them. Accelerometers were devices worn on the hip or thigh and did not include the more recent smartphone fitness apps.
The summary suggests that people designing exercise programmes could use monitors as a motivational tool within a more complex programme to encourage physical activity, rather than in isolation.
Why was this study needed?
Metabolic conditions such as type 2 diabetes are increasingly common, with 3.3 million diagnoses in the UK. Type 2 diabetes is closely linked to conditions such as overweight and obesity, and to cardiovascular disease. Improved diet and more physical activity are recommended as the first steps in managing these conditions.
The use of wearable technology is becoming a popular way to encourage people with cardiovascular or metabolic conditions to become more active. However, there is little high-quality evidence about the efficacy of these technologies, or how they can best be used. Previous reviews of the evidence have not looked specifically at people with at least one cardiometabolic condition, which often overlap.
This study was intended to be the most comprehensive review of the evidence in this group of people and to identify aspects of interventions which affected their efficacy.
What did this study do?
This was a systematic review and meta-analysis including 36 randomised controlled trials (RCTs) and 5,208 participants. Twenty studies assessed accelerometers and 16 used pedometers. Six studies were from the UK and nine from the US.
Eligible studies included adults aged 18 or over, with at least one of:
- type 2 diabetes or risk factors for type 2 diabetes
- obesity or overweight
- cardiovascular disease.
Researchers calculated the mean difference in physical activity levels where possible, but because of the use of different scales across studies, they reported overall results as standardised mean difference (SMD). They reported a difference in step count for the pedometer studies. Comparators included usual care, no intervention or minimal intervention. As the review only included RCTs, the results should be reliable.
What did it find?
- Interventions including monitoring devices (accelerometers or pedometers) resulted in a small to medium increase in physical activity over eight months compared with usual care or other interventions (SMD 0.39, 95% confidence interval [CI] 0.28 to 0.51; 22 studies, 4,856 participants).
- Pedometer-based interventions resulted in a medium increase in physical activity (SMD 0.52, 95% CI 0.32 to 0.72; 15 studies, 1,741 participants). This was an average increase of 1,703 steps per day compared with the control group (95% CI 1,067 to 2,339). Accelerometer-based interventions resulted in a small increase in physical activity compared with controls (SMD 0.30, 95% CI 0.16 to 0.44; 20 studies, 3,115 participants).
- Pedometer-based interventions that included face-to-face consultations with a healthcare professional showed the largest improvement in physical activity levels (SMD 0.73, 95% CI 0.50 to 0.97; 10 studies). The effect was smaller for accelerometer studies including consultations (SMD 0.29, 95% CI 0.14 to 0.43; 12 studies). Without support, pedometers had a small effect while accelerometers were ineffective.
- Other variables, such as diagnosis, age, length of intervention and use of goal setting were not associated with the effectiveness of the intervention. However, monitors showed a greater effect on physical activity levels in studies that included mostly male participants.
- Monitoring devices did not show any impact on secondary outcomes including glucose levels, blood pressure, cholesterol and body mass index.
What does current guidance say on this issue?
The UK’s four Chief Medical Officers published guidance in September 2019 on the amount of physical activity people should do. For adults, the advice is:
- To be physically active every day.
- To do activities to develop or maintain strength in the major muscle groups. Muscle-strengthening activities should be carried out on at least two days a week.
- Each week, accumulate at least 150 minutes of moderate-intensity activity or 75 minutes of vigorous-intensity activity or even shorter durations of very vigorous-intensity activity; or a combination of moderate, vigorous and very vigorous-intensity activity.
What are the implications?
The study suggests that staff setting up physical activity programmes for people with cardiometabolic disease might want to consider using pedometers as motivational tools, within a wider programme. Accelerometers seem less successful. Also, monitoring devices used without coaching or support from healthcare professionals do not work as well as those used within a programme.
Pedometers might be a relatively quick and cheap way to enhance a physical activity programme, but cannot replace such a programme on their own.
Citation and Funding
Department of Health and Social Care. UK Chief Medical Officers’ physical activity guidelines. London: Department of Health and Social Care; 2019.
Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre