The influence of maturation, body size and physical self-perceptions on longitudinal changes in physical activity in adolescent girls.

The aim of this study was to adopt a longitudinal design to explore the direct effects of both absolute and relative maturation and changes in body size on physical activity, and explore if, and how, physical self-perceptions might mediate this effect. We recruited 208 girls (11.8 ± 0.4 years) at baseline. Data were collected at three subsequent time points, each 6 months apart. At 18 months, 119 girls remained in the study. At each time point, girls completed the Physical Activity Questionnaire for Children, the Pubertal Development Scale (from which, both a measure of relative and absolute maturation were defined) and the Physical Self-Perception Profile, and had physical size characteristics assessed. Multilevel modelling for physical activity indicated a significant negative effect of age, positive effect for physical condition and sport competence and positive association for relatively early maturers. Absolute maturation, body mass, waist circumference and sum of skinfolds did not significantly contribute to the model. Contrary to common hypotheses, relatively more mature girls may, in fact, be more active than their less mature peers. However, neither changes in absolute maturation nor physical size appear to directly influence changes in physical activity in adolescent girls.

A longitudinal examination of the influence of maturation on physical self-perceptions and the relationship with physical activity in early adolescent girls.

This longitudinal study investigated the influence of maturation on physical self-perceptions and the relationship with physical activity in early adolescent girls (N=150; mean age=12.79+/-0.31). Physical characteristics were measured and participants completed the Physical Activity Questionnaire for Children, the Children and Youth Physical Self-Perception Profile and the Pubertal Development Scale on two occasions 12 months apart. The results demonstrated a decrease in overall physical activity levels over 12 months which was not influenced by maturational status or physical characteristics. Additional analysis indicated that physical self-perceptions partially accounted for the explained variance in physical activity change, with physical condition being an important individual predictor of physical activity. Further analysis indicated that body mass was an important individual predictor of changes in perceptions of body attractiveness and physical self-worth. At this age maturation has a limited influence on the physical activity behaviours of early adolescent girls and although the variance in physical activity was partly accounted for by physical self-perceptions, this was a relatively small contribution and other factors related to this drop in physical activity need to be considered longitudinally.

Impact of low-volume, high-intensity interval training on maximal aerobic capacity, health-related quality of life and motivation to exercise in ageing men.

There is a demand for effective training methods that encourage exercise adherence during advancing age, particularly in sedentary populations. This study examined the effects of high-intensity interval training (HIIT) exercise on health-related quality of life (HRQL), aerobic fitness and motivation to exercise in ageing men. Participants consisted of males who were either lifelong sedentary (SED; N = 25; age 63 ± 5 years) or lifelong exercisers (LEX; N = 19; aged 61 ± 5 years). [Formula: see text] and HRQL were measured at three phases: baseline (Phase A), week seven (Phase B) and week 13 (Phase C). Motivation to exercise was measured at baseline and week 13. [Formula: see text] was significantly higher in LEX (39.2 ± 5.6 ml kg min(-1)) compared to SED (27.2 ± 5.2 ml kg min(-1)) and increased in both groups from Phase A to C (SED 4.6 ± 3.2 ml kg min(-1), 95 % CI 3.1 - 6.0; LEX 4.9 ± 3.4 ml kg min(-1), 95 % CI 3.1-6.6) Physical functioning (97 ± 4 LEX; 93 ± 7 SED) and general health (70 ± 11 LEX; 78 ± 11 SED) were significantly higher in LEX but increased only in the SED group from Phase A to C (physical functioning 17 ± 18, 95 % CI 9-26, general health 14 ± 14, 95 % CI 8-21). Exercise motives related to social recognition (2.4 ± 1.2 LEX; 1.5 ± 1.0 SED), affiliation (2.7 ± 1.0 LEX; 1.6 ± 1.2 SED) and competition (3.3 ± 1.3 LEX; 2.2 ± 1.1) were significantly higher in LEX yet weight management motives were significantly higher in SED (2.9 ± 1.1 LEX; 4.3 ± 0.5 SED). The study provides preliminary evidence that low-volume HIIT increases perceptions of HRQL, exercise motives and aerobic capacity in older adults, to varying degrees, in both SED and LEX groups.

A qualitative examination of factors related to the decrease in physical activity behavior in adolescent girls during the transition from primary to secondary school.

BACKGROUND: Quantitative research has suggested that the decline in physical activity levels for adolescent girls is most marked during the transition from primary school to secondary school yet understanding the contributing factors for this decline may be advanced through qualitative research methods to gain an individual perspective of the girls' school transition experience. METHODS: This study explored factors related to the decrease in physical activity behavior in 14 adolescent girls (mean age = 13.6 ± 0.3 years) during the transition between primary and secondary school through the use of narrative interviews and interpretative phenomenological analysis. RESULTS: The findings suggested that a change in the environment was central to understanding the decline in physical activity levels since primary school. CONCLUSIONS: During secondary school, a positive environment can be created by ensuring a choice of activities in Physical Education lessons; allowing a girls-only environment, to reduce the focus on competence and competition, and recognizing the importance of social support. These could enhance self-perceptions, reduce self-presentational concerns, increase enjoyment, and subsequently reduce the decrease in physical activity behavior during this key transitional period.

Social physique anxiety and physical activity in early adolescent girls: the influence of maturation and physical activity motives.

In this study, we examined the influence of maturation on social physique anxiety, the relationship between social physique anxiety and current and future physical activity levels, and the influence of motives for physical activity on this relationship in early adolescent girls (n=162; mean age = 11.8 +/- 0.3 years). Participants completed the Pubertal Development Scale, the modified Social Physique Anxiety Scale, and the Motives for Physical Activity Scale at baseline and the Physical Activity Questionnaire for Older Children at baseline and 6 months later. The girls became less active across the 6 months and girls in the early stages of maturation had significantly lower social physique anxiety than the girls in the middle and late stages of maturation. Social physique anxiety was not related to current or future physical activity in the sample as a whole. Cluster analysis identified four groups with different motive profiles and the High Appearance and Fitness group demonstrated a moderate negative relationship between social physique anxiety and physical activity at phase 1, whereas the other groups did not. These findings indicate that social physique anxiety may increase with maturation and the relationship between social physique anxiety and physical activity is dependent on reasons for being active. For girls who are motivated to be active primarily by body-related reasons, social physique anxiety is likely to lead to lower levels of physical activity.