NCT03900962

Home-based Resistance Training for Adults With Severe Obesity

Effects of Adding Home-based Power Training to a Multidisciplinary Weight Management Service: A Randomised Clinical Trial

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 38 (actual)
• Sponsor: University of Hull · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This study evaluates whether adding home-based resistance training to a multidisciplinary specialist weight management service can promote weight loss and improve physical function, strength, power and quality of life in adults with severe obesity. The study also investigated whether performing resistance exercises as fast as possible can yield further improvements in physical function compared with traditional slow-speed resistance training. All recruited participants completed a 3-month home-based resistance training programme with behavioural support; half of the participants performed resistance exercises in a slow and controlled manner, whereas the other half performed resistance exercises with maximal intentional velocity.

Detailed description

Severe obesity reduces muscle contractile function, which manifests as a diminished ability to perform activities of daily living. These functional impairments often lead to pain during movement and a decreased motivation to exercise. In the United Kingdom (UK), specialist Tier 3 weight management services are provisioned for adults with severe obesity. Tier 3 services comprise a multidisciplinary team (MDT) of specialists and mainly adopt an educational approach, focusing on psychological therapy, dietary modification, pharmacotherapy and physical activity advice. However, current Tier 3 programmes do not specifically address the functional impairments imposed by obesity, which predisposes adults with severe obesity to musculoskeletal pain and pathology. Adding supervised resistance training to MDT weight management programmes has been shown to improve functional capacity in adults with severe obesity. However, supervised interventions place considerable time and resource burdens on the service provider and patient, which may not be conducive to sustained participation. Obese individuals often report feeling too embarrassed to exercise in front of others and feel uncomfortable appearing in public wearing exercise clothing. Home-based exercise is a convenient alternative to supervised interventions and may promote similar functional adaptations. Traditional resistance training typically involves sustained contractions at low to moderate velocities. While this method of training is effective for augmenting maximal strength production, which is executed at slow velocities, it may neglect the development of muscle power. This is problematic because lower-limb power has recently emerged as a critical determinant of function in adults with severe obesity. Power training integrates a high-speed component into conventional resistance training exercises. Research in older adults has consistently shown that power training is superior to conventional slow-speed strength training for improving functionality. Preliminary evidence also exists supporting the superiority of power training in sarcopenic obese adults. Nevertheless, it is unknown whether home-based power training is feasible or effective when added to an MDT weight management programme. The investigators recruited participants from a UK Tier 3 specialist weight management service. In a prospective, parallel groups, randomised design, participants were randomly allocated to a slow-speed strength training group or a high-speed power training group. Both groups completed a 12-week, individualised, home-based resistance training intervention (2x/week) with behavioural support. The high-speed power training group performed resistance exercises with maximal intended concentric velocity whereas the slow-speed strength training group maintained a slow (2-s) lifting speed. Outcomes were assessed at baseline, 3-month (post-intervention), and 6-month (follow-up) endpoints.

Conditions

• Obesity, Morbid

Interventions

Type	Name	Description
OTHER	Home-based resistance training	Patients completed two home-based resistance training sessions each week on non-consecutive days for 12 weeks. The programme was delivered online via individual playlists on Youtube (YouTube, San Bruno, California, USA), with each playlist involving an individually-prescribed series of pre-recorded exercise videos. Each session involved a dynamic warm-up followed by 11 resistance exercises using body weight and resistance bands, and finished with static stretching. Participants completed 1-2 sets of 5-12 repetitions at 4-7 on a modified 10-point rating of perceived exertion scale, which corresponded to qualitative descriptors of "moderate" to "hard". Resistance training stimuli were progressed weekly by increasing the external load, modifying the exercise selection, increasing the number of repetitions, and/or increasing the number of sets.
OTHER	Walking intervention	After the initial baseline assessment, participants recorded the number of steps they walked daily for seven days using a waist-worn pedometer. Participants maintained their usual physical activity levels during this period. Participants were then encouraged to increase their total steps walked each day by 5% each week during the 12-week intervention.

Timeline

• Start date: 2017-01-09
• Primary completion: 2018-05-18
• Completion: 2018-08-24
• First posted: 2019-04-03
• Last updated: 2023-08-24