Pediatrics published research on the effects of physical training combined with growth hormone (GH) on muscle thickness and its relationship with muscle strength and motor development in 22 infants with Prader-Willi syndrome (PWS) followed over 2 years.
Muscle thickness was measured using ultrasound. Muscle strength was assessed using the Infant Muscle Strength meter. Finally, motor development was evaluated using the Gross Motor Function Measure.
The results indicated the following:
1. muscle thickness was significantly decreased in the biceps brachii, forearm flexors, quadriceps, and tibialis anterior muscles in infants with PWS and growth hormone treatment increases muscle thickness in infants with PWS.
2. Muscle thickness changes with increasing age in the biceps brachii and tibialis anterior was similar to typical development
3. muscle thickness changes in the quadriceps and forearm flexors was higher compared to typical development.
4. all 4 muscle groups showed significant positive effects of growth hormone on muscle thickness when controlled for age and baseline muscle thickness.
5. significant correlations between muscle thickness and muscle strength was recorded, between muscle thickness and motor development, and between muscle strength and motor development.
The researchers recommend the following:
"To increase muscle strength and improve motor skills in PWS infants, physical training should be an integrated aspect of daily life. Therefore, we recommend a physical therapy program in which parents learn how to stimulate their infant's motor development by providing a playful learning environment in which the influence of gravity is attuned to their child's constrained motor abilities. Moreover, we recommend an exercise repetition level of 10 repetitions as optimal, because this allows skill learning combined with a training stimulus to increase muscle strength."
Linda Reus, Sigrid Pillen, Ben J. Pelzer, Janielle A.A.E.M. van Alfen-van der Velden, Anita C.S. Hokken-Koelega, Machiel Zwarts, Barto J. Otten, and Maria W.G. Nijhuis-van der Sanden. Growth Hormone Therapy, Muscle Thickness, and Motor Development in Prader-Willi Syndrome: An RCT. Pediatrics 2014; 134:6 e1619-e1627; published ahead of print November 24, 2014, doi:10.1542/peds.2013-3607
Boggs, W. MD. Growth Hormone Boosts Muscle Thickness, Motor Development In Prader-Willi Syndrome. Healthy Living Magazine. Retrieved from the web on 12/4/14 at http://www.healthylivingmagazine.us/Articles/5681/