Effect of long-term leisure time physical activity on lean mass and fat mass in girls during adolescence

Bidirectional associations between adiposity and physical activity: a longitudinal study from pre-puberty to early adulthood

Objective

This study aimed to investigate directional influences in the association between adiposity and physical activity (PA) from pre-puberty to early adulthood.

Methods

In the Calex-study, height, weight, body fat and leisure-time physical activity (LTPA) were measured at age11.2-years, 13.2-years and 18.3-years in 396 Finnish girls. Body fat was measured by dual-energy X-ray absorptiometry, calculating fat mass index (FMI) as total fat mass in kilograms divided by height in meters squared. LTPA level was evaluated using a physical activity questionnaire. In the European Youth Heart Study (EYHS), height, weight and habitual PA were measured at age 9.6-years, 15.7-years and 21.8-years in 399 Danish boys and girls. Habitual PA and sedentary behaviour were assessed with an accelerometer. Directional influences of adiposity and PA were examined using a bivariate cross-lagged path panel model.

Results

The temporal stability of BMI from pre-puberty to early adulthood was higher than the temporal stability of PA or physical inactivity over the same time period both in girls and boys. In the Calex-study, BMI and FMI at age 11.2-years were both directly associated with LTPA at age 13.2-years (β = 0.167, p = 0.005 and β = 0.167, p = 0.005, respectively), whereas FMI at age 13.2-years showed an inverse association with LTPA at age 18.3-years (β = - 0.187, p = 0.048). However, earlier LTPA level was not associated with subsequent BMI or FMI. In the EYHS, no directional association was found for physical inactivity, light-, moderate-, and vigorous-PA with BMI during the follow-up in girls. In boys, BMI at age 15.7-years was directly associated with moderate PA (β = 0.301, p = 0.017) at age 21.8-years, while vigorous PA at age 15.7-years showed inverse associations with BMI at age 21.8-years (β = - 0.185, p = 0.023).

Conclusion

Our study indicates that previous fatness level is a much stronger predictor of future fatness than level of leisure-time or habitual physical activity during adolescence. The directional associations between adiposity and physical activity are not clear during adolescence, and may differ between boys and girls depending on pubertal status.

Changes in physical activity over the lifespan: impact on body composition and sarcopenic obesity

Physical activity and body composition show a typical pattern over the lifecycle. Fat-free mass and physical performance generally peak in early adulthood. Here, evidence for a relation between physical activity changes over the life span and the development of sarcopenic obesity is presented. Activity-induced energy expenditure increases with body size and physical activity during growth. The physical activity level, calculated by expressing total energy expenditure as a multiple of resting energy expenditure, gradually increases from early age to adulthood to decrease again in old age. Habitual physical activity has a significant effect on growth of fat-free mass during adolescence and thus on peak fat-free mass and physical performance in early adulthood. Older subjects have a lower fat-free mass and lower physical activity levels but there is no association, suggesting physical activity does not protect against loss of lean body mass at higher age. Prevention of sarcopenic obesity starts with a physically active lifestyle to develop a healthy peak fat-free mass and subsequent prevention of excess fat gain. The change from a physically active to a more sedentary routine in later life requires restriction of energy intake to maintain energy balance.

Association of leisure time physical activity and NMR-detected circulating amino acids in peripubertal girls: A 7.5-year longitudinal study

This study investigated the longitudinal associations of physical activity and circulating amino acids concentration in peripubertal girls. Three hundred ninety-six Finnish girls participated in the longitudinal study from childhood (mean age 11.2 years) to early adulthood (mean age 18.2 years). Circulating amino acids were assessed by nuclear magnetic resonance spectroscopy. LTPA was assessed by self-administered questionnaire. We found that isoleucine, leucine and tyrosine levels were significantly higher in individuals with lower LTPA than their peers at age 11 (p < 0.05 for all), independent of BMI. In addition, isoleucine and leucine levels increased significantly (~15%) from childhood to early adulthood among the individuals with consistently low LTPA (p < 0.05 for both), while among the individuals with consistently high LTPA the level of these amino acids remained virtually unchanged. In conclusion, high level of physical activity is associated lower serum isoleucine and leucine in peripubertal girls, independent of BMI, which may serve as a mechanistic link between high level of physical activity in childhood and its health benefits later in life. Further studies in peripubertal boys are needed to assess whether associations between physical activity and circulating amino acids in children adolescents are sex-specific.

Normal-weight obesity and cardiometabolic risk: A 7-year longitudinal study in girls from prepuberty to early adulthood

OBJECTIVE

To study whether normal-weight obesity in childhood is associated with increased cardiometabolic risk in early adulthood.

METHODS

This study assessed data for 236 girls followed from prepuberty to early adulthood. Growth chart data were obtained from birth to 18 years. Body composition was assessed by dual-energy x-ray absorptiometry and cardiometabolic risk by calculating continuous clustered risk score (at ages 11, 14, and 18). The association of body weight status with cardiometabolic risk from childhood to early adulthood was examined.

RESULTS

Subjects with normal-weight obesity were virtually indistinguishable from their normal-weight lean peers in terms of relative body weight and BMI but had significantly higher fat mass (7.1-7.3 kg) and cardiometabolic risk already in childhood, and this difference persisted into early adulthood (P <  0.001 for all).

CONCLUSIONS

Children and adolescents with normal body weight and high body fat percentage may be at increased risk for cardiometabolic morbidity in adulthood. Body fatness may be of utility in clinical practice to effectively identify children and adolescents at risk and to permit recommendation of lifestyle changes that could translate to lower risks of cardiovascular diseases in the future.

Serum Amino Acid Profiles in Childhood Predict Triglyceride Level in Adulthood: A 7-Year Longitudinal Study in Girls

CONTEXT

Branched-chain and aromatic amino acids are associated with high risk of developing dyslipidemia and type II diabetes in adults.

OBJECTIVE

This study aimed to examine whether serum amino acid profiles associate with triglyceride concentrations during pubertal growth and predict hypertriglyceridemia in early adulthood.

DESIGN

This was a 7.5-year longitudinal study.

SETTING

The study was conducted at the Health Science Laboratory, University of Jyväskylä.

PARTICIPANTS

A total of 396 nondiabetic Finnish girls aged 11.2 ± 0.8 years at the baseline participated in the study.

MAIN OUTCOME MEASURES

Body composition was assessed by dual-energy x-ray absorptiometry; serum concentrations of glucose, insulin, and triglyceride by enzymatic photometric methods; and amino acids by nuclear magnetic resonance spectroscopy.

RESULTS

Serum leucine and isoleucine correlated significantly with future triglyceride, independent of baseline triglyceride level (P < .05 for all). In early adulthood (at the age of 18 years), these amino acids were significantly associated with hypertriglyceridemia, whereas fat mass and homeostasis model assessment of insulin resistance were not. Leucine was the strongest determinant discriminating subjects with hypertriglyceridemia from those with normal triglyceride level (area under the curve, 0.822; 95% confidence interval, 0.740-0.903; P = .000001).

CONCLUSIONS

Serum leucine and isoleucine were associated with future serum triglyceride levels in girls during pubertal growth and predicted hypertriglyceridemia in early adulthood. Therefore, these amino acid indices may serve as biomarkers to identify individuals at high risk for developing hypertriglyceridemia and cardiovascular disease later in life. Further studies are needed to elucidate the role these amino acids play in the lipid metabolism.

Windows of opportunity for physical activity in the prevention of obesity

Tackling increasing rates of obesity is likely to be a defining feature of health care over the next several decades. Adult obesity is a persistent and treatment-resistant problem. Consequently, an emerging theme in the literature is to commence prevention efforts earlier in the developmental time course. This view is based primarily on epidemiological data demonstrating a link between traits manifesting early during development and increased obesity risk in adulthood. Physical activity is a perennial factor in discussions of obesity prevention. However, the optimal timing and type of physical activity interventions to commence remains unclear. Critical developmental windows of plasticity may afford time-limited opportunities to shape body composition across the life course; however, physical activity has not been explicitly considered in these discussions. Although animal models suggest that physical activity commenced earlier in development has differential effects on obesity onset compared to physical activity commenced in adulthood, human research is lacking. In this conceptual review, we consider physical activity during critical developmental periods as a way to mitigate obesity risk later in life.

Does serum 25-hydroxyvitamin D influence muscle development during puberty in girls? A 7-year longitudinal study

Vitamin D is well known for its regulatory role in calcium and phosphate homeostasis, but its role in muscle mass and strength during growth remains inconclusive. We explored the association of serum 25-hydroxyvitamin D (25(OH)D) with muscle development in girls from 11 to 18-years old. Whole body lean tissue mass (LMWB), appendicular lean mass (aLM), muscle cross-sectional area at the lower leg (mCSA), maximal voluntary contraction of elbow flexors (MVC elbow) and knee extensors (MVC knee) were assessed in 217 girls aged 10-13 years (at baseline), 215 in 2-year and 226 in 7.5-year follow-up. Serum concentration of 25(OH)D and intact parathyroid hormone (PTH) were analyzed retrospectively and girls were categorized according to their 25(OH)D levels (consistently insufficient 25(OH)D GLL <50 nmol/l and consistently sufficient GHH >50 nmol/l from baseline to 7-year follow-up). We found that 25(OH)D level declined until menarche (p<0.05) while LMWB, aLM, mCSA, MVC elbow and MVC knee continued to increase (p<0.001 for all) post menarche. At pre-menarche, the GLL (n = 34) had higher LMWB and aLM than the GHH (n = 21, p<0.05), while post-menarche the GHH (n = 15) had a greater catch-up gain in LMWB (p = 0.004), aLM (p = 0.001) and mCSA (p = 0.027) compared to the GLL (n = 65) over the first 2-year period. At the age of 18, no differences in muscle mass/strength between the low (n = 151) and high (n = 77) levels of 25(OH)D groups were found. This finding was independent of vitamin D receptor genotype and other confounders. In conclusion, our results showed that levels of 25(OH)D have no significant negative influence on the development of muscle mass and strength during pubertal growth both with longitudinal and cross-sectional comparison. On the contrary, our results suggest that the temporary negative association between 25(OH)D and muscle mass arises as a consequence of fast growth prior to menarche, and this negative association is diminished through catch-up growth after menarche.