Aerobic capacity, strength, flexibility, and activity level in unimpaired extremely low birth weight (≤800 g) survivors at 17 years of age compared with term-born control subjects

Objectives. To compare aerobic capacity, strength, flexibility, and activity level in extremely low birth weight (ELBW) adolescents at 17 years of age with term-born control subjects. Methods. Fifty-three ELBW teens of birth weight <= 800 g were assessed at 17.3 years (16.3 - 19.7 years; birth weight: 720 g [520 - 800 g]; gestation: 26 weeks [23 - 29 weeks]) along with term- born control subjects (n = 31) at age 17.8 years (16.5 - 19.0 years; birth weight: 3506 g [3068 4196 g]; gestation: weeks 40 [39 - 42 weeks]). ELBW and control teens were assessed by a pediatric physiotherapist and completed components of the Canadian Physical Activity, Fitness and Lifestyle Appraisal and a self- assessment fitness and activity questionnaire. Continuous data were analyzed using MANOVA (group, gender) followed by t tests; categorical data were analyzed using the chi(2) test. Results. ELBW teens had lower aerobic capacity, grip strength, leg power, and vertical jump; could do fewer push- ups; had less abdominal strength as measured by curl- ups; had less lower back flexibility; and had tighter hamstrings. ELBW teens reported less previous and current sports participation, lower physical activity level, and poorer coordination compared with term-born control subjects. ELBW teens were also found to have more difficulty with maintenance of rhythm and cadence. Although ELBW teens rated themselves lower on all measures of sporting activity, they were as happy with their level of fitness as the control subjects. Conclusions. Compared with term-born control subjects, there are significant differences in motor performance in unimpaired ELBW survivors in late adolescence, reflected in aerobic capacity, strength, endurance, flexibility, and activity level. We conclude that these differences in fitness and physical activity are related to the interaction of effects of premature birth on the motor system together with a more inactive lifestyle. These findings have potential implications for later adult health problems.