title: Physical activity and maximal oxygen uptake in adults with Prader-Willi syndrome.
abstract: BACKGROUND
  Prader-Willi Syndrome (PWS) is the most common genetic syndrome causing life-threatening obesity. Strict adherence to a low-calorie diet and regular physical activity are needed to prevent weight gain. Direct measurement of maximal oxygen uptake (VO2max), the "gold standard" for assessing aerobic exercise capacity, has not been previously described in PWS.
  
  
  OBJECTIVE
  Assess aerobic capacity by direct measurement of VO2max in adults with PWS, and in age and BMI-matched controls (OC), and compare the results with values obtained by indirect prediction methods.
  
  
  METHODS
  Seventeen individuals (12 males) age: 19-35 (28.6 ± 4.9) years, BMI: 19.4-38.1 (27.8 ± 5) kg/m2with genetically confirmed PWS who exercise daily, and 32 matched OC (22 males) age: 19-36 (29.3 ± 5.2) years, BMI: 21.1-48.1 (26.3 ± 4.9) kg/m2. All completed a medical questionnaire and performed strength and flexibility tests. VO2max was determined by measuring oxygen consumption during a graded exercise test on a treadmill.
  
  
  RESULTS
  VO2max (24.6 ± 3.4 vs 46.5 ± 12.2 ml/kg/min, p < 0.001) and ventilatory threshold (20 ± 2 and 36.2 ± 10.5 ml/kg/min, p < 0.001), maximal strength of both hands (36 ± 4 vs 91.4 ± 21.2 kg, p < 0.001), and flexibility (15.2 ± 9.5 vs 26 ± 11.1 cm, p = 0.001) were all significantly lower for PWS compared to OC. Predicted estimates and direct measurements of VO2max were almost identical for the OC group (p = 0.995), for the PWS group, both methods for estimating VO2max gave values which were significantly greater (p < 0.001) than results obtained by direct measurements.
  
  
  CONCLUSIONS
  Aerobic capacity, assessed by direct measurement of VO2max, is significantly lower in PWS adults, even in those who exercise daily, compared to OCs. Indirect estimates of VO2max are accurate for OC, but unreliable in PWS. Direct measurement of VO2should be used for designing personal training programs and in clinical studies of exercise in PWS.
authors.affiliation: Department of Pediatrics, Hadassah Medical Center, Ein Kerem, Kiryat Hadassah, POB 12000, 91120, Jerusalem, Israel. itaigross@gmail.com.
authors.forename: Itai
authors.initials: I
authors.lastname: Gross
authors.affiliation: Israel Multidisciplinary PraderWilli Syndrome Clinic, Neuropediatric Unit, Department of Pediatrics, Shaare Zedek Medical Center, Jerusalem, Israel.|Neuropediatric Unit, Department of Pediatrics, Shaare Zedek Medical Center, Jerusalem, Israel.
authors.forename: Harry J
authors.initials: HJ
authors.lastname: Hirsch
authors.affiliation: Sports Medicine Center, Department of Orthopedic Surgery, Hadassah Medical Center, Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Naama
authors.initials: N
authors.lastname: Constantini
authors.affiliation: Sports Medicine Center, Department of Orthopedic Surgery, Hadassah Medical Center, Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Shachar
authors.initials: S
authors.lastname: Nice
authors.affiliation: The School of Education, Hebrew University, Jerusalem, Israel.
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Pollak
authors.affiliation: Israel Multidisciplinary PraderWilli Syndrome Clinic, Neuropediatric Unit, Department of Pediatrics, Shaare Zedek Medical Center, Jerusalem, Israel.|Neuropediatric Unit, Department of Pediatrics, Shaare Zedek Medical Center, Jerusalem, Israel.
authors.forename: Larry
authors.initials: L
authors.lastname: Genstil
authors.affiliation: Israel Multidisciplinary PraderWilli Syndrome Clinic, Neuropediatric Unit, Department of Pediatrics, Shaare Zedek Medical Center, Jerusalem, Israel.|The Hebrew University Faculty of Medicine, Jerusalem, Israel.|Reproductive Endocrinology and Genetics Unit, Department of Obstetrics and Gynecology, Shaare Zedek Medical Center, Jerusalem, Israel.
authors.forename: Talia
authors.initials: T
authors.lastname: Eldar-Geva
authors.affiliation: Israel Multidisciplinary PraderWilli Syndrome Clinic, Neuropediatric Unit, Department of Pediatrics, Shaare Zedek Medical Center, Jerusalem, Israel.|Neuropediatric Unit, Department of Pediatrics, Shaare Zedek Medical Center, Jerusalem, Israel.|The Hebrew University Faculty of Medicine, Jerusalem, Israel.
authors.forename: Varda Gross
authors.initials: VG
authors.lastname: Tsur
mesh_terms: D000328:Adult; D015992:Body Mass Index; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology*; D011218:Prader-Willi Syndrome / Q000503:physiopathology*; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Aerobic exercise capacity; Prader–Willi syndrome; VO2 max