Tailored Exercise May Benefit Obese PWS Patients, Case Study Suggests

Obese people with Prader-Willi syndrome (PWS) should have access to exercise training programs different from those of obese people not affected by PWS, a case report suggests.

The case study, “Differences in Aerobic Fitness between an Obese Adolescent with Prader-Willi Syndrome and Other Obese Adolescents and Exercise Training Results,” was published in the International Journal of Environmental Research and Public Health.

PWS is the most common genetic cause of morbid obesity in children. Studies indicate that obese PWS patients have lower aerobic capacity, meaning their heart and lungs are not able to efficiently get oxygen to the muscles.

Although limited caloric intake and exercise regimens are crucial to prevent excess weight gain and worsening of obesity-related complications, physical exercise can be difficult for people with PWS.

Researchers at Kaohsiung Veterans General Hospital in Taiwan described the case of a 17-year old obese PWS patient who was referred for exercise training programs. In addition to PWS, he had a history of precocious puberty, high cholesterol, uric acid in the blood, and an abnormally curved spine (scoliosis).

The patient had intentionally lost weight before admission, dropping from 120 kg to 106 kg in a month. Subsequent tests found high blood pressure and abnormal levels of lipids (fats) in the blood — called dyslipidemia. Both were treated with appropriate therapies.

The patient underwent cardiopulmonary exercise testing and body composition examination, including measurements of height, body weight, heart rate, and oxygen consumption.

Results showed that his aerobic fitness capacity was diminished, so the team prescribed a two-week, in-hospital exercise training program.

The patient did aerobic exercises daily, and one-hour sessions of anaerobic exercise — short, fast, high-intensity exercise that does not require oxygen as an energy source — three days a week.

For the aerobic part of the program, doctors recommended an up-and-down step exercise. The anaerobic part entailed moderate fatigue exercise with thoracic expansion exercises such as side and trunk extension, as well as core muscle training, including Superman, leg raise, plank, and crunch. The patient performed eight to 15 submaximal repetitions of each exercise.

Results at the end of the two weeks showed that all aspects of the patient’s cardiopulmonary performance had improved, including oxygen consumption and workload, but his body composition remained practically the same. His body weight dipped from 106.1 kg to 104.4 kg (from about 234 pounds to 230 pounds).

The patient’s aerobic fitness was compared with that of 13 age-matched, obese males without PWS. Even with the improvements after the training program, the controls’ aerobic capacity was still markedly better than that of the PWS patient.

The patient was discharged with a prescription for a home exercise program.

The study suggests that aerobic fitness evaluation could be based on cardiopulmonary testing, which would then help health professionals refer patients to appropriate training programs.

“Due to the relatively declined aerobic fitness, the designs and prognosis of exercise training programs for PWS patients should be different from those of ordinary obese patients,” the team wrote.

“Meanwhile, PWS patients could benefit from CPET [cardiopulmonary exercise testing] for aerobic fitness evaluation,” they added.