Factors Affecting Indigenous West Australians' Health Behavior: Indigenous Perspectives.

The factors driving the disparity in health outcomes between Indigenous and non-Indigenous Australians include socio-economic factors, racism, and history. The current study focused on exploring Indigenous participants' perspectives of the factors that affect the health behavior of their community members. Participatory action research methodology and a grounded theory approach were utilized. In total, 120 members of two urban West Australian Indigenous communities participated in focus group discussions. There was substantial similarity between the themes that emerged within the discussions held in the two communities. Factors relating to culture, social connections, racism, communication, and personal aspects were particularly salient to health behavior of the participants. Several of the themes including culture, racism, communication, and distrust highlight the tension caused by being a member of a minority cultural group that has been marginalized by the practices and attitudes of the dominant cultural group. Personal choice was sometimes prioritized over health.

The Dynamic Family Home: a qualitative exploration of physical environmental influences on children's sedentary behaviour and physical activity within the home space.

BACKGROUND: Recent changes in home physical environments, such as decreasing outdoor space and increasing electronic media, may negatively affect health by facilitating sedentariness and reducing physical activity. As children spend much of their time at home they are particularly vulnerable. This study qualitatively explored family perceptions of physical environmental influences on sedentary behaviour and physical activity within the home space. METHODS: Home based interviews were conducted with 28 families with children aged 9-13 years (total n = 74 individuals), living in Perth, Australia. Families were stratified by socioeconomic status and selected to provide variation in housing. Qualitative methods included a family interview, observation and home tour where families guided the researcher through their home, enabling discussion while in the physical home space. Audio recordings were transcribed verbatim and thematically analysed. RESULTS: Emergent themes related to children's sedentariness and physical activity included overall size, space and design of the home; allocation of home space; equipment within the home space; perceived safety of the home space; and the changing nature of the home space. Families reported that children's activity options were limited when houses and yards were small. In larger homes, multiple indoor living rooms usually housed additional sedentary entertainment options, although parents reported that open plan home layouts could facilitate monitoring of children's electronic media use. Most families reported changing the allocation and contents of their home space in response to changing priorities and circumstances. CONCLUSIONS: The physical home environment can enhance or limit opportunities for children's sedentary behaviour and physical activity. However, the home space is a dynamic ecological setting that is amenable to change and is largely shaped by the family living within it, thus differentiating it from other settings. While size and space were considered important, how families prioritise the use of their home space and overcome the challenges posed by the physical environment may be of equal or greater importance in establishing supportive home environments. Further research is required to tease out how physical, social and individual factors interact within the family home space to influence children's sedentary behaviour and physical activity at home.

A place for play? The influence of the home physical environment on children's physical activity and sedentary behaviour.

The home environment is an important influence on the sedentary behaviour and physical activity of children, who have limited independent mobility and spend much of their time at home. This article reviews the current evidence regarding the influence of the home physical environment on the sedentary behaviour and physical activity of children aged 8-14 years. A literature search of peer reviewed articles published between 2005 and 2011 resulted in 38 observational studies (21 with activity outcomes, 23 with sedentary outcomes) and 11 experimental studies included in the review. The most commonly investigated behavioural outcomes were television watching and moderate to vigorous physical activity. Media equipment in the home and to a lesser extent the bedroom were positively associated with children's sedentary behaviour. Physical activity equipment and the house and yard were not associated with physical activity, although environmental measures were exclusively self-reported. On the other hand, physical activity equipment was inversely associated with sedentary behaviours in half of studies. Observational studies that investigated the influence of the physical and social environment within the home space, found that the social environment, particularly the role of parents, was important. Experimental studies that changed the home physical environment by introducing a television limiting device successfully decreased television viewing, whereas the influence of introducing an active video game on activity outcomes was inconsistent. Results highlight that the home environment is an important influence on children's sedentary behaviour and physical activity, about which much is still unknown. While changing or controlling the home physical environment shows promise for reducing screen based sedentary behaviour, further interventions are needed to understand the broader impact of these changes. Future studies should prioritise investigating the influence of the home physical environment, and its interaction with the social environment, on objectively measured sedentary time and home context specific behaviours, ideally including technologies that allow objective measures of the home space.

Does exercise duration affect Fatmax in overweight boys?

To compare the assessment of Fat(max) using a single graded exercise test with 3 min stages against 30 min prolonged exercise bouts in overweight boys. Ten overweight boys (8-12 years) attended the laboratory on seven separate occasions. On the first visit, body anthropometrics and peak aerobic capacity ([Formula: see text]O(2peak)) were assessed. Following this, each participant attended the laboratory after an overnight fast for six morning cycling sessions. During the first session, participants completed a continuous, submaximal graded exercise protocol with seven 3 min stages (GRAD) at 35, 40, 45, 50, 55, 60 and 65% [Formula: see text]O(2peak). The final five visits consisted of a 30 min bout of prolonged exercise (PROL) performed in a counterbalanced order at 40, 45, 50, 55 and 60% [Formula: see text]O(2peak). There was no effect of exercise duration on Fat(max) or the absolute rate of fat oxidation during PROL (p > 0.05). At the group level, GRAD and PROL provided similar estimates of Fat(max) (GRAD: 53 ± 10% [Formula: see text]O(2peak); PROL: 53 ± 10% [Formula: see text]O(2peak); p = 0.995); however, individual variation between the two protocols is shown by a systematic bias and residual error of 0 ± 11% [Formula: see text]O(2peak). Fat oxidation rates remained stable across 30 min of steady-state exercise in overweight boys. Furthermore, Fat(max) was similar at 3, 10, 20 and 30 min of exercise, suggesting that for exercise lasting ≤ 30 min, exercise duration does not affect Fat(max). However, Fat(max) determined with GRAD may need to be interpreted with caution at the individual level given the variation in Fat(max) between protocols.

Selected physical capacity norms for Australian football players at the non-elite level.

Australian football is a popular male team sport that consists mainly of participants competing at the non-elite level. The main purpose of this study was to compare in non-elite Australian football players competing in sub-elite and community leagues, selected physical capacities recognised as predictors of lower extremity injury in Australian football and/or other sports. Participants were 143 adult (mean age of 22.2 years) male Western Australian footballers from the Western Australian Football League (WAFL) (sub-elite) and the Western Australian Amateur Football League (WAAFL) (community). During the 2005 regular playing season participants completed a questionnaire and a physical measurement testing session. The physical testing session involved the following lower extremity measures: generalised joint laxity, leg length discrepancy, presence of Morton's toe, foot arch, hamstring flexibility and static balance. Football players from the sub-elite and community leagues did not differ significantly in any of the physical testing session measures or in the questionnaire items relating to injury number in the past 12 months and lower limb preventative device use. However, they did differ in some measures with players from the sub-elite league significantly more likely to stretch after a match and training, and to have a designated stretching leader at their club. While players from the community league were significantly more likely to smoke and to participate in sports additional to Australian football. Although the selected physical capacities did not differ between the sub-elite and community players in this study, future research should be aimed at identifying differences for a greater number of physical capacities, including skill and endurance, while utilising a larger sample.

Simplifying the star excursion balance test: analyses of subjects with and without chronic ankle instability.

STUDY DESIGN: Case control study. OBJECTIVES: The objectives of this study are: (1) to perform factor analyses on data from the 8 components of the star excursion balance test (SEBT) in subjects with and without chronic ankle instability (CAI) in an effort to reduce the number of components of the SEBT, (2) to assess the relationships between performance of the different reach directions using correlation analyses, and (3) to determine which components of the SEBT are most affected by CAI. BACKGROUND: The SEBT is a series of 8 lower-extremity-reaching tasks purported to be useful in identifying lower extremity functional deficits. METHODS AND MEASURES: Forty-eight young adults with unilateral CAI (22 males, 26 females; mean +/- SD age, 20.9 +/- 3.2 years; mean +/- SD height, 173.6 +/- 11.1 cm; mean +/- SD mass, 80.1 +/- 22.1 kg) and 39 controls (23 males, 16 females; mean +/- SD age, 20.7 +/- 2.4 years; mean +/- SD height, 174.1 +/- 12.9 cm; mean +/- SD mass, 75.1 +/- 18.6 kg) performed 3 trials of the 8 tasks with each of their limbs. Separate exploratory factor analyses were performed on data for involved limbs of the CAI group, uninvolved limbs of the CAI and control groups, and both limbs of the CAI and control groups. Pearson product moment correlations were calculated to identify the relationships between the different reach directions. A series of eight 2 x 2 analyses of variance were calculated to determine the influence of group (CAI, control) and side (involved, uninvolved) on performance of the 8 tasks. RESULTS: For all 3 factor analyses, only 1 factor in each analysis produced an eigenvalue greater than 1 and the posteromedial reach score was the most strongly correlated task with the computed factor (alpha > .90), although all 8 tasks produced alpha scores greater than .67. Bivariate correlations between specific reach directions ranged from .40 to .91. Subjects with CAI reached significantly less on the anteromedial, medial, and posteromedial directions when balancing on their involved limbs compared to their uninvolved limbs and the side-matched limbs of controls. CONCLUSIONS: The posteromedial component of the SEBT is highly representative of the performance of all 8 components of the test in limbs with and without CAI. There is considerable redundancy in the 8 tasks. The anteromedial, medial, and posteromedial reach tasks may be used clinically to test for functional deficits related to CAI in lieu of testing all 8 tasks. There is a need for a hypothesis-driven study to confirm the results of this exploratory study.

Development of a Kinect Software Tool to Classify Movements during Active Video Gaming.

While it has been established that using full body motion to play active video games results in increased levels of energy expenditure, there is little information on the classification of human movement during active video game play in relationship to fundamental movement skills. The aim of this study was to validate software utilising Kinect sensor motion capture technology to recognise fundamental movement skills (FMS), during active video game play. Two human assessors rated jumping and side-stepping and these assessments were compared to the Kinect Action Recognition Tool (KART), to establish a level of agreement and determine the number of movements completed during five minutes of active video game play, for 43 children (m = 12 years 7 months ± 1 year 6 months). During five minutes of active video game play, inter-rater reliability, when examining the two human raters, was found to be higher for the jump (r = 0.94, p < .01) than the sidestep (r = 0.87, p < .01), although both were excellent. Excellent reliability was also found between human raters and the KART system for the jump (r = 0.84, p, .01) and moderate reliability for sidestep (r = 0.6983, p < .01) during game play, demonstrating that both humans and KART had higher agreement for jumps than sidesteps in the game play condition. The results of the study provide confidence that the Kinect sensor can be used to count the number of jumps and sidestep during five minutes of active video game play with a similar level of accuracy as human raters. However, in contrast to humans, the KART system required a fraction of the time to analyse and tabulate the results.

Factors Influencing the Health Behaviour of Indigenous Australians: Perspectives from Support People.

Disparities between the health of Indigenous and non-Indigenous populations continue to be prevalent within Australia. Research suggests that Indigenous people participate in health risk behaviour more often than their non-Indigenous counterparts, and that such behaviour has a substantial impact on health outcomes. Although this would indicate that reducing health risk behaviour may have positive effects on health outcomes, the factors that influence Indigenous health behaviour are still poorly understood. This study aimed to interview people who support Indigenous groups to gain an understanding of their views on the factors influencing health behaviour within Indigenous groups in Western Australia. Twenty nine people participated in the study. The emergent themes were mapped against the social ecological model. The results indicated that: (1) culture, social networks, history, racism, socioeconomic disadvantage, and the psychological distress associated with some of these factors interact to affect health behaviour in a complex manner; (2) the desire to retain cultural identity and distinctiveness may have both positive and negative influence on health risk behaviour; (3) strong social connections to family and kin that is intensified by cultural obligations, appears to affirm and disrupt positive health behaviour; (4) the separation between Indigenous and non-Indigenous social connection/networks that appeared to be fostered by marginalisation and racism may influence the effect of social networks on health behaviour; and (5) communication between Indigenous and non-Indigenous people may be interrupted by distrust between the groups, which reduces the influence of some non-Indigenous sources on the health behaviour of Indigenous people.

Lower extremity malalignments and anterior cruciate ligament injury history.

To identify if lower extremity malalignments were associated with increased propensity of a history of anterior cruciate ligament (ACL) ruptures in males and females using a case control design. Twenty subjects (10 males, 10 females) had a history of ACL injury and twenty (10 males, 10 females) had no history of ACL injury. Subjects were assessed for navicular drop, quadriceps angle, pelvic tilt, hip internal and external rotation range of motion, and true and apparent leg length discrepancies. Statistical analysis was performed to identify differences in these measures in regard to injury history and gender, and to identify if any of these measures were predictive of ACL injury history. Increased navicular drop and anterior pelvic tilt were found to be statistically significant predictors of ACL injury history regardless of gender. Limbs that had previously suffered ACL ruptures were found to have increased navicular drop and anterior pelvic tilt compared to uninjured limbs. Based on the results of this retrospective study, the lower extremity malalignments examined do not appear to predispose females to tearing their ACLs more than males. Key PointsHyperpronation and greater anterior pelvic tilt were the two malalignments most associated with history of ACL injury.Females had larger quadriceps angles than males, but this measure was not significantly related to ACL injury history.Not all structural differences between genders help explain the increased risk of ACL injuries in female athletes.

The effect of social support on the health of Indigenous Australians in a metropolitan community.

The factors driving the disparity in health outcomes between Indigenous and non-Indigenous Australians continue to be poorly understood. Despite this, studies confirm that social connections are a very important part of Indigenous life, and it is likely these connections play an important role in influencing health outcomes among this population. Examining the support provided by social connections in relation to health behaviour may assist our understanding of health outcomes among Indigenous Australians. The current study is focused on exploring Indigenous participants' impressions of their social network and social support using Participatory Action Research methodology and qualitative methods. The objective was to identify the influence of social support on the health outcomes of Indigenous people within a Western Australian metropolitan community. Seventeen members of the community were interviewed during the study. The participants had extensive social networks that mainly comprised members of their kinship group. The consequences of this social network included: (1) the positive effects of social support from bonded relationships; (2) the negative effects of social support produced by over-obligation and unidirectional support involving bonded relationships; (3) limited or inadequate social support caused by withdrawal from bonded relationships; (4) lack of social support from bridging relationships; and (5) a strong desire for connection and a sense of belonging.

Does movement proficiency impact on exergaming performance?

There is growing interest in the use of consumer level exergames in movement skill acquisition. The purpose of this study was to investigate the relationship between movement proficiency and performance in virtual exergaming. Twenty seven children, aged 10-15years participated in an experiment completing the Movement Assessment Battery for Children 2 (MABC-2) and a series of XBOX360 Kinect Sports exergaming tasks. Significant correlations were observed between MABC-2 aiming and catching percentile and exergame javelin and target kick, where the more proficient movers tended to perform better in the exergame. Statistically significant correlations were observed between MABC-2 balance percentile and exergaming sprint and target kick performance. In this study children who scored better in real life gross motor movement tasks performed better in most related exergaming activities. This suggests current exergaming technology has advanced to a point where body movement unencumbered by a physical or remote game device tether can extract movements resembling real life tasks, translate them into game play and reward proficient movers with higher in-game performance. It is possible that benefit gained in an exergaming environment by more proficient movers was a result of either their more proficient movement, or a greater ability to adapt to the exergame.

Effects of electrostimulation therapy on recovery from acute team-sport activity.

PURPOSE: To assess the efficacy of a 1-off electrostimulation treatment as a recovery modality from acute team-sport exercise, directly comparing the benefits to contrast water therapy. METHODS: Ten moderately trained male athletes completed a simulated team-game circuit (STGC). At the conclusion of exercise, participants then completed a 30-min recovery modality of either electrostimulation therapy (EST), contrast water therapy (CWT), or a passive resting control condition (CON). Twenty-four hours later, participants were required to complete a modified STGC as a measure of next-day performance. Venous blood samples were collected preexercise and 3 and 24 h postexercise. Blood samples were analyzed for circulating levels of interleukin-6 (IL-6) and C-reactive protein (CRP). RESULTS: The EST trial resulted in significantly faster sprint times during the 24-h postrecovery than with CON (P < .05), with no significant differences recorded between EST and CWT or between CWT and CON (P > .05). There were no differences in IL-6 or CRP across all trials. Finally, the perception of recovery was significantly greater in the EST trial than in the CWT and CON (P < .05). CONCLUSIONS: These results suggest that a 1-off treatment with EST may be beneficial to perceptual recovery, which may enhance next-day performance.

Life after the game--injury profile of past elite Australian football players.

OBJECTIVES: To investigate the long-term health and well-being of past elite Australian Football League (AFL) players, with particular emphasis on the effect of playing injuries on current lifestyle. DESIGN: Cross sectional survey. METHODS: A health and well-being survey, completed by past AFL players (n=592) with mean (±SD) age of 55.1 y (±15.8) and playing career of 7.7 y (±4.1) sought information on demographics, education and employment, subjective well-being, lifestyle behaviours, physical health, disease prevalence, community and social structures, and playing history. RESULTS: A majority of past players experienced serious injuries (76%) and concussion (73%) throughout their career, both increasing significantly with the number of games played. Of those who received injuries, 60% require on-going treatment, yet only 6% receive treatment costs covered by their club or the AFL Players' Association. A large proportion (64%) of respondents are affected in daily life from previous AFL injuries. CONCLUSIONS: AFL careers are compounded by high injury rates, including loss of consciousness with a high incidence of multiple concussions amongst those players reporting a serious injury. Greater number of injuries received will further the likelihood of requiring on-going treatment and being affected later in life. Additional research and planning may be important in assisting other improvements in the quality of life of past AFL players.

New-Generation Active Videogaming Maintains Energy Expenditure in Children Across Repeated Bouts.

OBJECTIVE: Active videogames (AVGs) remain popular among 10-15-year-old children. The Xbox 360 Kinect™ from Microsoft (Redmond, WA) represents a new generation of AVGs where body movements are used to control gameplay. The purpose of this study was to measure energy expenditure required to play repeated bouts of six Microsoft Xbox 360 Kinect games ("Motion Sports Adrenaline™," "Sonic Free Riders™," "Virtua Tennis 4™," "Kinect Sports™," "Kinect Adventures™," and "Just Dance 3™"). SUBJECTS AND METHODS: Forty-seven children (between 10 and 15 years) participated in a repeated-measures experiment, completing five 1-hour sessions (one familiarization and four separate gaming sessions). Three different AVGs were played for 15 minutes during each gaming session in a counterbalanced order. An Actiheart (CamNtech Ltd., Cambridge, United Kingdom) was used to monitor heart rate and acceleration during gameplay. RESULTS: Average energy expended across the six AVGs during 15 minutes of gameplay was 3.0±0.17 metabolic equivalents/minute, significantly higher than resting energy expenditure (P<0.01). Similar levels of energy expenditure were observed between the first and fourth gaming session for all six games, although the energy expenditure between each game over the four sessions was similar. Boys expended more energy than girls within each AVG and across the four gaming sessions. CONCLUSIONS: The Microsoft Xbox 360 Kinect games in this study were found to elicit moderate-intensity exercise over four gaming sessions, with no decay in energy expenditure over several gaming sessions. Although small differences in the energy expenditure between the six Microsoft Xbox Kinect games were found, they are all likely to contribute toward reduced sitting time in children.

Can we teach moderate intensity activity? Adult perception of moderate intensity walking.

OBJECTIVES: To investigate how people determine the intensity of their physical activity, respond to instruction, and their understanding of moderate intensity walking. DESIGN: Experimental. METHODS: Forty nine regular walkers had their walking speed, heart rate and rate of perceived exertion measured during their normal walking behaviour, when instructed to walk at a moderate intensity, and after provision of feedback on how to meet moderate intensity walking. RESULTS: Although moderate intensity walking was generally perceived as too low to be beneficial, walking speed was the best variable matched across all experiments for moderate intensity (83.7%, 67.3% and 93.9%), followed by heart rate, with a large proportion of participants responding favourably to instruction relating to heart rate and speed to meet moderate intensity walking. Rate of perceived exertion was a poor reflector of walking intensity. CONCLUSION: Most participants naturally selected a walking intensity that elicits moderate intensity and when instructed to walk at moderate intensity, the intensity is more vigorous. Attempting to match speed and heart rate limits for moderate intensity reduced the intensity perceived by participants.

The epidemiology of injury among surfers, kite surfers and personal watercraft riders: wind and waves.

The objective of this review was to summarize the epidemiological literature for surfboard riding (surfing), kite surfing and personal watercraft (PWC) riding injuries and describe the incidence and nature of these injuries, common risk factors, and strategies for prevention. The databases searched for relevant publications included Medline, ScienceDirect, ProQuest International, PubMed, Academic Search Premier as well as Google Scholar to identify additional, non-indexed studies. Overall, there was a lack of good quality descriptive studies for these three sports and many of the studies reviewed involved the use of administrative datasets or case-series designs. Among the few studies to provide incidence estimates, there were inconsistencies in how injury was defined, the inclusion criteria, and the reporting of incidence rates, making comparisons within and between the sports difficult. While the reported incidence rates were generally low, head and lower extremity injuries were common across all three sports. Only two studies reported evidence for postulated risk factors. Bigger waves and surfing over rock or reef sea floor increased the risk of injury among competitive surfers, while older age and having more experience increased the risk of significant injuries among recreational surfers. No evaluations of preventative measures were identified. This review demonstrates the need for well-designed epidemiological research, especially studies that focus on the accurate measurement and description of incidence, nature, severity and circumstances of injuries. Once this has occurred, interventions targeted at reducing the incidence of injuries among these sports can be designed, implemented and evaluated.

Optimising sprint interval exercise to maximise energy expenditure and enjoyment in overweight boys.

The aim of this study was to identify the sprint frequency that when supplemented to continuous exercise at the intensity that maximises fat oxidation (Fat(max)), optimises energy expenditure, acute postexercise energy intake and enjoyment. Eleven overweight boys completed 30 min of either continuous cycling at Fat(max) (MOD), or sprint interval exercise that consisted of continuous cycling at Fat(max) interspersed with 4-s maximal sprints every 2 min (SI(120)), every 1 min (SI(60)), or every 30 s (SI(30)). Energy expenditure was assessed during exercise, after which participants completed a modified Physical Activity Enjoyment Scale (PACES) followed by a buffet-type breakfast to measure acute postexercise energy intake. Energy expenditure increased with increasing sprint frequency (p < 0.001), but the difference between SI(60) and SI(30) did not reach significance (p = 0.076), likely as a result of decreased sprint quality as indicated by a significant decline in peak power output from SI(60) to SI(30) (p = 0.034). Postexercise energy intake was similar for MOD, SI(120), and SI(30) (p > 0.05), but was significantly less for SI(60) compared with MOD (p = 0.025). PACES was similar for MOD, SI(120), and SI(60) (p > 0.05), but was less for SI(30) compared with MOD (p = 0.038), SI(120) (p = 0.009), and SI(60) (p = 0.052). In conclusion, SI(60) appears optimal for overweight boys given that it maximises energy expenditure (i.e., there was no additional increase in expenditure with a further increase in sprint frequency) without prompting increased energy intake. This, coupled with the fact that enjoyment was not compromised, may have important implications for increased adherence and long-term energy balance.

Adding sprints to continuous exercise at the intensity that maximises fat oxidation: implications for acute energy balance and enjoyment.

The objective was to examine the effect of adding sprints to continuous exercise at the intensity that maximises fat oxidation (Fat(max)) on energy expenditure, substrate oxidation, enjoyment and post-exercise energy intake in boys. Nine overweight and nine normal weight boys (8-12 years) attended the laboratory on three mornings. First, body anthropometrics, peak aerobic capacity and Fat(max) were assessed. On the remaining two sessions, resting metabolic rate was determined before participants completed 30 min of either continuous cycling at Fat(max) (MOD) or sprint interval exercise consisting of continuous cycling at Fat(max) interspersed with four-second maximal sprints every two minutes (SI). Energy expenditure and substrate oxidation were measured during exercise and for 30 min post-exercise, while participants completed a modified Physical Activity Enjoyment Scale (PACES). This was followed by a buffet-like breakfast to measure post-exercise energy intake. Fat oxidation rate was similar between groups and protocols (P>0.05). Both groups expended more energy with SI compared to MOD, resulting from increased carbohydrate oxidation (P<0.05), which was not compensated by increased energy intake. Participants indicated that they preferred SI more than MOD, although there was no significant difference in PACES score between the protocols (P>0.05). In summary, the addition of short sprints to continuous exercise at Fat(max) increased energy expenditure without compromising fat oxidation or stimulating increased post-exercise energy intake. The boys preferred SI and did not perceive it to be any harder than MOD, indicating that sprint interval exercise should be considered in exercise prescription for this population.

Substrate oxidation in overweight boys at rest, during exercise and acute post-exercise recovery.

OBJECTIVE: To compare substrate oxidation between normal weight (n = 10) and overweight (n = 10) boys at rest, during exercise at 50% VO(2peak) and during the first 30 minutes of recovery post-exercise. STUDY DESIGN: Twenty boys (8-11 years) were tested over two separate occasions. At the first session, body composition was measured by Dual-Energy X-ray Absorptiometry and peak aerobic capacity (VO(2peak)) was assessed using an incremental treadmill protocol. At least one week later, substrate oxidation was determined via indirect calorimetry in the fasted state at rest, during 10 minutes of exercise at 50% VO(2peak) and during the first 30 minutes of acute recovery post-exercise. RESULTS: There were no significant differences in substrate oxidation between the two groups at rest or during exercise. However, during early recovery, respiratory exchange ratio (RER) transiently increased in the overweight boys (p = 0.034) but not in the normal weight boys (p = 0.796), with a shift towards greater carbohydrate oxidation in the former group at 15-20 (p = 0.044) and 25-30 (p = 0.052) minutes post-exercise. In contrast, absolute post-exercise fat oxidation was similar between the two groups. CONCLUSION: Overweight boys may oxidise fat less efficiently than normal weight boys during recovery post-exercise, deriving a greater proportion of energy from carbohydrate oxidation.

Effect of a sand or firm-surface walking program on health, strength, and fitness in women 60-75 years old.

The effects of 8 wk of soft-sand (n = 19) and firm-surface walking (n = 19) on blood lipids, submaximal fitness (8-min walk at 4.5 km/hr), and leg strength in elderly (60+ yr), sedentary women were studied. Significant main time effects (p < .005) were found for blood lipids. The surface interaction effect for high-density lipoprotein approached significance (p = .052), with a tendency for higher levels in the sand group postintervention (p = .06). Neither group reported significant differences across time for submaximal oxygen consumption (p = .223), but a greater percentage reduction in heart-rate response to the 8-min walk was reported in the sand group (p = .016). Knee strength did not change in either group, whereas hip strength significantly improved in both groups (p = .0001), with larger effect sizes reported in the sand group. Overall, both groups showed improvements in blood lipids, fitness, and strength, with strength changes being slightly higher in the sand-walking group.