Improving Muscle Strength and Muscle Mass in People with Prader-Willi Syndrome

Lay Abstract

We will test if a type of exercise called progressive strength training can make the muscles of people with Prader-Willi syndrome (PWS) stronger and bigger. In this type of exercise, people lift weights a small number of times before their muscles get tired and as people get stronger the amount of weight they lift is increased. We will recruit 15 people with PWS aged 14 years and older, and by chance, get half to do progressive strength training and half to do a non-strengthening exercise program supervised by a physical therapist. The non-strengthening exercise program will get participants to lift light weights but the amount of weight will not be progressed or increased. All participants will exercise at their local community gym twice a week for 24 weeks. A clinician who does not know which group the participants are in will measure the strength and size of participants’ arm and leg muscles, and also how active they are and what community activities they take part in. Measurements will be taken before and after exercising and also 6 months later at one of three testing centers.

People with PWS have muscles that are up to 70% weaker and up to 40% smaller than people without disability. This makes movement difficult, and means people with PWS are less likely to want to exercise. It can also make day-to-day life hard for them including being physically active, and controlling their weight. Research shows that progressive strength training make muscles stronger and bigger for people in the general population and also for people with disabilities, such as Down syndrome and cerebral palsy. However, it is not known if this type of exercise is good for people with PWS. Three small studies of people with PWS have tested the effect of other types of exercise on muscle strength and size, but there are many faults in the way these studies were done. The main problem is that the exercises were not challenging enough to make muscles stronger. We want to find out if 6-months of progressive strength training can make the muscles of people with PWS stronger and bigger.

We also want to find out if having bigger and stronger muscles in people with PWS makes it easier for them to do daily tasks. We will begin by recruiting 15 participants and if we are successful with a second year of funding we will expand our participant numbers to 30. We intend to use the data we collect to help get US or Australian government funding to expand our trial to 60 participants with PWS.

We will use the outcomes of our study to improve clinical care by developing online resources and examples of best practice to help families, exercise professionals, community gyms and health agencies implement progressive strength training for people with PWS. We will share our results widely and in different formats so as to reach a board, diverse audience. We will continue our research to find the best way to support people with PWS to exercise to improve their lives.

*Funded in partnership with the Australian Government and the PW Research Foundation of Australia