Body composition, cardiorespiratory and musculoskeletal fitness in obese adolescents aged 14 to 18 years old

Background. The short and long term consequences of childhood obesity are widespread, highlighting the necessity of designing effective interventions targeting the specific needs of obese adolescents. Obese children typically score lower on standardized fitness tests compared to their leaner peers. However, few studies have looked at the relationship between musculoskeletal fitness and obesity in adolescents. Sex differences in fitness and adiposity are important considerations that also warrant further investigation.;Methods. (1) 134 female and 45 male participants were included in the analysis. Musculoskeletal fitness was assessed by the Canadian Physical Activity Fitness and Lifestyle Approach guidelines to assess muscular strength, endurance and power. Measures of grip strength, push-ups, curl-ups, sit and reach and vertical jump in the HEARTY study were compared to the Canadian Musculoskeletal norms in their age group. (2) 94 female and 30 male participants were included in the analysis. VO2peak was assessed using a maximal treadmill protocol until exhaustion and abdominal adiposity was quantified by one-single cross-sectional image at L4-L5 by Magnetic Resonance Imaging.;Results. (1) Obese adolescents ranked lower on most musculoskeletal fitness tests compared to their non-obese peers. However, obese females had greater grip strength compared to their non-obese female counterparts. Males in the HEARTY study had a higher grip strength and vertical jump whereas females had higher push-up, and sit and reach scores than males in the HEARTY study. (2) HEARTY males had a greater BMI, visceral adipose tissue and higher VO2peak compared to females. There was no difference in abdominal subcutaneous adipose tissue between sexes.;Conclusions. (1) Male and female obese adolescents have lower musculoskeletal fitness compared to their non-obese peers. Obese males also had a lower overall musculoskeletal fitness ranking compared to obese females in the HEARTY study. (2) Obese male adolescents have greater visceral fat and higher cardiorespiratory fitness than obese females. However, it appears that the negative relationship between cardiorespiratory fitness and fatness is similar between male and female obese adolescents.;Objectives. (1) To compare the musculoskeletal fitness of obese adolescents in the Healthy Eating Aerobic and Resistance Training in Youth (HEARTY) trial to the norms of the Canadian population in the same age group. A secondary objective was to determine the sex differences in musculoskeletal fitness in the HEARTY study. (2) To determine the sex differences in abdominal adiposity and cardiorespiratory fitness in male and female participants in the HEARTY study. The secondary purpose was to examine the relationship between cardiorespiratory fitness and fatness in male and female obese adolescents.