Measuring physical literacy for an evidence-based approach: Validation of the French perceived physical literacy instrument for emerging adults.

Background/Objectives: Physical Literacy (PL) is increasingly recognized as a key element in studies aimed at promoting Physical Activity (PA), but measurement tools for emerging adults and evidence for assessing and using this concept is lacking in a wide range of contexts. We aimed to validate the French version of the Perceived Physical Literacy Instrument (PPLI): a scale for investigating PL in young French adults. Methods: After PL and PA data collection (n = 2,248, agemean = 19 ± 1.53 yrs), exploratory and confirmatory factor analyses, Cronbach's α and Omega's ω and an Intraclass-Correlation analysis were undertaken. Spearman's rank correlation and the Boruta algorithm were used to investigate the association between PL and PA. Boruta's algorithm examined deeper external validation by analyzing the strength of an overall PL score in explaining PA, compared with separate dimensions of PL and individual characteristics (BMI, sex). Results: Results showed an acceptable level of reliability (ICC = 0.91), internal validity (α = 0.88; ω = 0.77), and external validity (Rhô >0.18, p < 0.01). The Boruta algorithm highlighted that the construct of PL is a significant predictor of PA, although not the strongest one which is social and affective dimension. Conclusion: This study provided data on validity and reliability of the first French assessment tool to measure PL constituted by four intertwined dimensions (physical, cognitive, social, affective). At the same time, it provides new evidence of the association between PL and PA.

Catch me if you can! How French adolescents seize social occasions and opportunities to be active.

BACKGROUND: Following an ecological framework, the aim of this study was to highlight the way adolescents invested their time in opportunities to engage in moderate to vigorous physical activity (MVPA) according to whether they were profiled as more or less active. This study's innovation lies in the analysis of MVPA according to social occasions which are understood as opportunities to be active throughout the day (e.g. home, school, transport). METHODS: PA data measured by accelerometry (ActiGraph GT3X) for seven consecutive days were compiled, with adolescents' social occasions during the week recorded in a daily digital diary (n = 135). The opportunity ratio of MVPA at each social time is the ratio between time spent in MVPA and the duration of a corresponding social occasion. Following the literature, participants were categorised into three profiles according to their reported amount of MVPA: HEPA active, minimally active and inactive. Non-parametric Wilcoxon signed rank and Kruskal Wallis tests were performed to determine the relative intensity of PA performed at different social occasions, and to investigate whether intensities differed between adolescents with various activity profiles. RESULTS: Results showed that engagement in MVPA at different social occasions differed according to participant profiles. Mismatch was noticed between the opportunity ratio and the duration of the most and least favorable social occasions for MVPA. For all three profiles, the social occasion "physical education lesson" revealed an opportunity ratio of MVPA (23.6% vs 17.0% vs 13.8%) significantly higher than the overall opportunity ratio of the week (6.9% vs 2.9% vs 1.2%), but of lower duration. Conversely, "home" (5.3% vs 0.0% vs 0.0%) and "school" (outside of PE time) (2.4% vs 0.0% vs 0.0%) represented the two least opportune social occasions for PA in an adolescent's week. CONCLUSIONS: Rethinking engagement with MVPA in the context of temporal opportunities would allow potential ways to intervene within an educational supervised setting to help young people adopt a physically active lifestyle at the end of the key period of adolescence. These results reinforced the importance of context in interventions for PA promotion, opening for "time education" in people.

Building the Foundation of Aquatic Literacy in 4-6 Years-Old Children: A Systematic Review of Good Pedagogical Practices for Children and Parents.

Children between the ages of 4-6 years represent the population most affected by drowning accidents, while their early involvement in physical activity, and more specifically in aquatic activities is a key factor in their future physical life journey. The systematic review's purpose was to identify aspects in the intervention's studies with children and/or their parents that had a significant impact on the Aquatic Literacy (AL) dimensions mentioned as motor, psychological, affective, and cognitive. The PICO method was used to define the research question and PRISMA checklist searched for articles in nine databases: Cochrane, Embase, ERIC, ProQuest, PsychInfo, PubMed, Scopus, SportDiscus, and Web of Science. Eligibility criteria were: (1) English language, (2) primary research, (3) population of 4-6 year old children or their parents, (4) intervention study design, and (5) results related to at least one of the AL domains. The strength of evidence and the risk of bias were assessed. Results showed relatively poor number of studies for such a vulnerable population regarding the drowning risk (n = 8 for parents and n = 14 for children intervention). Studies did not show a consensus on which educational approach was more beneficial than others. Concerning parental education, results were rather homogeneous, especially concerning the theoretical frameworks employed and the relevancy to include parents in swimming programs. The development of pedagogical tools for promotion and evaluation, based on the AL theoretical framework, could help to clarify the question of "how to teach" children to prevent drowning and engage young children in long-term physical activities.

Complementing subjective with objective data in analysing expertise: A machine-learning approach applied to badminton.

This study aimed to assess which combination of subjective and empirical data might help to identify the expertise level. A group of 10 expert coaches classified 40 participants in 5 different expertise groups based on the video footage of the rallies. The expertise levels were determined using a typology based on a continuum of 5 conative stages: (1) structural, (2) functional, (3) technical, (4) contextual, and (5) expertise. The video allowed empirical measurement of the duration of the rallies, and tri-axial accelerometers measured the intensity of the player's involvement. A principal component analysis showed that two dimensions explained 54.9% of the total variance in the data and that conative stage and empirical parameters during rallies (duration, intensity of the game) were correlated with axis 1, whereas duration and acceleration data between rallies were correlated with axis 2. A random forest algorithm showed that among the parameters considered, acceleration, duration of the rallies, and time between rallies could predict conative stages with a prediction accuracy above possibility. This study suggests that performance analysis benefits from the confrontation of subjective and objective data in order to design training plans according to the expertise level of the participants.

Evaluation of Global Health in Master Swimmers Involved in French National Championships.

BACKGROUND: Swimming is often recommended as a means of increasing physical activity and gaining health benefits. The present study examined the psychological, social, and physical health states in competitive swimmers engaged in long-term training. METHODS: The study took place during the 4 days of the French master championships in France in 2011 (from 10 to 13 March). Global health parameters were evaluated and compared with general values reported in studies aiming to describe health standard values in France or Europe. All swimmers selected for the event were invited to participate in the study. Setting questionnaires concerning mental and social health (short form 36), physical activity (International Physical Activity Questionnaire), and medication were administered. Peak expiratory flow (l.min-1) was measured, and body mass index (kg.m-2) was calculated from height (m) and body mass (kg). Prevalence of overweight and obesity was calculated by age and gender. Chi-squared tests were used to compare prevalence of overweight and obesity between participants and reference values. Short form 36 scores and physical activity (met.h.week-1) were compared with reference values by single t-tests. Two-way ANOVA was used to compare peak flow results with standard values. The level of significance was set at p < 0.05. RESULTS: Out of 1554 master swimmers, 490 participated in this study (rates of participation = 44.8 and 23.5 % for females and males, respectively). Data showed inequality of health indexes as compared with reference values, despite a significantly higher level of physical activity including swimming activity. The prevalence of obesity was significantly lower (p < 0.05), and peak expiratory flow values were higher among female swimmers (from 7.6 to 17 % higher according to the age, p < 0.05). Perception of vitality was significantly higher for all female swimmers and the older age groups of male swimmers (p < 0.05). Perception of bodily pain indicated significantly lower scores for swimmers than the reference values (p < 0.05). Significantly lower prevalence of swimmers taking medication was noted in comparison with the French national values (p = 0.012). CONCLUSIONS: Compared with reference data from various sources, master competitive swimmers used less medication, had lower rates of obesity in most age groups, had greater peak expiratory flow values suggesting improved lung function, had higher levels of total physical activity, and had more favorable scores for various subscales of the SF-36. The results argue in favor of competitive swimming for its positive effects on health outcomes. KEY POINTS: French master swimmers involved in national championships have many positive health outcomes in terms of weight management, respiratory function, and vitality. However, the very high physical activity level in this competitive context did not result in significantly better levels on all parameters in comparison with their national counterparts (pain perception, social, emotional, and mental health).Positive health outcomes were higher for female master swimmers in terms of weight management, respiratory function, and vitality.The fact that these benefits were not linked with medication consumption could be interesting in an economic context aimed at controlling expenditures on health. Based on these data, we can argue for promoting this form of physical activity across the lifespan.

Examining self-training procedures in leisure swimming.

This study investigated contents of training sessions from 387 regular swimmers involved in a recreational workout without supervision. We did use multiple correspondences analysis in order to identify self-trained swimmers typology in a sample from a social networking website, focusing on swimming practice. Self-reported parameters (n = 12) were age, gender, practice frequency, supervision in physical activity experiment, main training target, main reason for swimming choice, swimming session duration and distance, most used swimming stroke and material, quality of the training control, and training evolution during a year. Results have highlighted different training strategies and targets according to gender and age. Male strategy consists in performing higher distance (1818.8 ± 644.5 m vs. 1453.0 ± 603.3, p < 0.05 for male and female respectively) by using several swim stroke and gears involving upper body muscles (front crawl, pull buoy and paddles). More concerned about duration of their sessions, women are mainly using breaststroke. Backstroke is associated with people aged higher than 50. We also have established a connection between motives according to ages and long term strategies. The main motivation for middle aged people appears to be general health benefits by performing identical swimming session without evolution during a year. People aged from 20 to 30 are divided between an identical swimming session strategy and an increase in distance or in intensity strategy during a year. This population appears to be concerned about a global health benefits and a body shape effects. Suggestions are made to improve swimming practice environment during free time sessions according to the main results. Key PointsMale strategy consists in performing higher distance by using several swim stroke and gears involving upper body muscles whereas women are more concerned about effort duration and use breaststroke in majority.The main motivation for middle aged people appears to be general health benefits whereas people aged from 20 to 30 appears to be concerned about a global health benefits and a body shape effects.Excepted middle age people, recreational swimmers have low control quality of their session even if they have a good skill level. This suggests to improve health strategy education and swimming pool environment.

Effects of a 6-week plyometric training program on performances in pubescent swimmers.

This study examined in pubescent swimmers the effects on front crawl performances of a 6-week plyometric training (PT) in addition to the habitual swimming program. Swimmers were assigned to a control group (n = 11, age: 14.1 ± 0.2 years; G(CONT)) and a combined swimming and plyometric group (n = 12, age: 14.3 ± 0.2 years; GSP), both groups swimming 5.5 h · wk(-1) during a 6-week preseason training block. In the GSP, PT consisted of long, lateral high and depth jumps before swimming training 2 times per week. Pre and posttests were performed by jump tests (squat jump [SJ], countermovement jump [CMJ]) and swim tests: a gliding task, 400- and 50-m front crawl with a diving start (V400 and V50, m · s(-1)), and 2 tests with a water start without push-off on the wall (25 m in front crawl and 25 m only with kicks). Results showed improvement only for GSP for jump tests (Δ = 4.67 ± 3.49 cm; Δ = 3.24 ± 3.17 cm; for CMJ and SJ, respectively; p < 0.05) and front crawl tests (Δ = 0.04 ± 0.04 m · s(-1); Δ = 0.04 ± 0.05 m · s(-1); for V50 and V400, respectively; p < 0.05). Significant correlations were found for GSP between improvements in SJ and V50 (R = 0.73, p < 0.05). Results suggested a positive effect of PT on specific swimming tasks such as dive or turn but not in kicking propulsion. Because of the practical setup of the PT and the relevancy of successful starts and turns in swimming performances, it is strongly suggested to incorporate PT in pubescent swimmers' training and control it by jump performances.

Effect of stroke rate reduction on swimming technique during paced exercise.

The purpose of this study is to analyze the acute adaptations of motor organization subsequent to a reduction in spontaneous stroke rate (SR) at different swimming speeds, a task constraint that is currently used by trainers to improve stroke technique. Ten well-trained swimmers (8 males and 2 females, whose mean swimming speed on a 400-m front crawl stroke represents 76.8 ± 3.7% and 73.3 ± 2.7% of the mean speed of the short-course pool world record, respectively) performed 3 sets of 3 time to exhaustion trials in front crawl at paces corresponding to 95%, 100%, and 110% of the mean speed measured in a 400-m race. During the first set, individual SR was continuously recorded and averaged. During the second set (Fixed), participants were constrained to swim at their individual corresponding SR. For the third set (Lowered), an individual corresponding SR value lowered by 5% was imposed. Durations of trials and arm stroke phases durations were analyzed. The results showed that the durations of the whole trials declined significantly from the Fixed set to the Lowered set (p < 0.05). Swimmers spent more time in the nonpropulsive phases (increases ranged from 8.6-13.2%; p < 0.05), and the duration of the propulsive phases did not differ significantly in the lowered set. The significant decline in exercise durations might have been caused by an unusual muscular solicitation. Swimming technique changes during trials in the Fixed set suggest an increase in magnitude and efficiency in the propulsive force and a better body streamlining to limit an increase of the resistive impulse in between arm propelling actions. In conclusion, these results should be taken into account to better define training-set technical benefits and better include the impact of such task constraints into the training schedule.

Changes in swimming technique during time to exhaustion at freely chosen and controlled stroke rates.

The aim of this study was to assess technical changes during constrained swimming in time-to-exhaustion tests. Ten swimmers of national standard performed a maximal 400-m front crawl and two sets of exhaustion tests at 95%, 100%, and 110% of mean 400-m speed. In the first set (free), swimmers had to maintain their speeds until exhaustion and mean stroke rate was recorded for each test. In the second set (controlled), the same speed and individual corresponding stroke rate were imposed. The durations of the exhaustion tests, relative durations of the stroke phases, and arm coordination were analysed. For each speed in the "controlled" set, the exhaustion tests were shorter. Moreover, variables were consistent, suggesting a stabilization of stroke technique. Under the free condition, stroke rate increased to compensate for the decrease in stroke length. At the same time, swimmers reduced the relative duration of their non-propulsive phases in favour of the propulsive phases. Thus, swimmers changed their arm coordination, which came close to an opposition mode. These two constraints enable swimmers both to maintain their stroking characteristics and develop compensatory mechanisms to maintain speed. Moreover, stroke rate can be seen as a useful tool for controlling arm technique during paced exercise.

Propulsion and braking in the study of asymmetry in able-bodied men's gaits.

The present study was designed to test functional differences between both lower limbs in able-bodied gait according to fore-aft force impulse analyses and to assess the existence of a preferential lower limb for forward propulsion and braking. The leg that did more of the braking (Most Braking Limb) and the leg that did more of the propulsion (Most Propulsive Limb) were defined by the higher negative and positive impulses calculated from the anterior-posterior component of the ground reaction force. 24 adult men free of pain and injury to their lower extremities (M age =25.9 yr., SD=4.5) performed 10 walking trials on a 10-m walkway with two force plates flush mounted in the middle. The anterior-posterior component of the velocity of the center of mass (V(AP)) was calculated with the VICON system. Results highlighted two forms of asymmetry behaviour: although significant bilateral differences between the legs concerning the propulsive and braking impulses were found in all participants, 70.8% of the participants displayed a different Most Braking Limb than Most Propulsive Limb, whereas 25% used the same leg to produce both more propulsion and braking. High consistency was found in the behavioural strategy. Bilateral differences in V(AP) according to the gait cycle (Most Propulsive Limb vs Most Braking Limb) suggested a functional division of tasks between the two lower limbs for 70.8% of the participants. The study provides support for the relevancy of a functional categorization to highlight different asymmetry strategies in able-bodied gait.

Using effect size to quantify plantar pressure asymmetry of gait of nondisabled adults and patients with hemiparesis.

In the literature, numerous statistical analyses are used to quantify asymmetry in gait. This study tested the effect size (ES) statistic for quantifying asymmetry in nondisabled and pathological populations. The plantar pressure peaks on eight footprint locations of 27 nondisabled subjects and 18 patients with hemiparesis were bilaterally compared. Asymmetry quantifications were performed with ES and standard statistical tests (index of asymmetry, symmetry index, and ratio index). The results show an advantage in using ES to quantify asymmetry when confidence limits are also calculated. Conversely, traditional asymmetry indexes immediately implied asymmetry without statistical basis. These findings should be considered when one is attempting to diagnose pathological walking patterns or guide rehabilitation processes.

Aerobic potential, stroke parameters, and coordination in swimming front-crawl performance.

The purposes of this review were (1) to review the recent studies conducted in swimming on the assessment of aerobic potential and establishment of exercise-intensity domains (it is important that exercise-intensity domains be accurately defined and their physiological underpinnings well understood to optimize and evaluate training programs); (2) to analyze changes in traditionally measured stroke rate and stroke length during exhaustive swims, particularly in relation to the predetermined intensity domains (introduction of an "optimal swimming technique speed"); and (3) to introduce the latest swimming research on arm coordination that might help us better understand the technical adaptations of swimmers under physical stress.