The exercise effect on psychological well-being in older adults—a systematic review of longitudinal studies

The aim of this systematic review was to investigate the longitudinal relationship between physical activity (PA) and the psychological domains of well-being in older adults and to identify possible moderators and mediators of this relationship. Twelve longitudinal investigations were included in this review. The results indicate that there seems to be a positive association between PA and psychological well-being over time. Thus PA may be one possible individual lifestyle factor for the long-term promotion of psychological well-being in older adults. Especially leisure time PA at light intensities conducted in group settings was identified to be beneficial for promoting psychological well-being. Furthermore, longitudinal results indicated that self-efficacy, self-esteem, affect, optimism, and pre-interventional motivation moderated/mediated the relationship between PA and psychological well-being in older adults.     

The effect of caffeine ingestion on 8 km run performance in a field setting

Abstract

The aim of this study was to assess the effect of caffeine ingestion on 8 km run performance using an ecologically valid test protocol. A randomized double-blind crossover study was conducted involving eight male distance runners. The participants ran an 8 km race 1 h after ingesting a placebo capsule, a caffeine capsule (3 mg · kg^?1 body mass) or no supplement. Heart rate was recorded at 5 s intervals throughout the race. Blood lactate concentration and ratings of perceived exertion were recorded after exercise. A repeated-measures analysis of variance (ANOVA) identified a significant treatment effect for 8 km performance time (P < 0.05); caffeine resulted in a mean improvement of 23.8 s (95% confidence interval [CI] = 13.1 to 34.5 s) in 8 km performance time (1.2% improvement, 95% CI = 0.7 to 1.8%). In addition, a two-way (time × condition) repeated-measures ANOVA identified a significantly higher blood lactate concentration 3 min after exercise during the caffeine trial (P < 0.05). We conclude that ingestion of 3 mg · kg^?1 body mass of caffeine can improve absolute 8 km run performance in an ecologically valid race setting.     

Does exercise have a protective effect on cognitive function under hypoxia? A systematic review with meta-analysis

ObjectiveThis study aimed to examine (1) the independent effects of hypoxia on cognitive function and (2) the effects of exercise on cognition while under hypoxia.MethodsDesign: Systematic review with meta-analysis. Data sources: PubMed, Scopus, Web of Science, PsychInfo, and SPORTDiscus were searched. Eligibility criteria for selecting studies: randomized controlled trials and nonrandomized controlled studies that investigated the effects of chronic or acute exercise on cognition under hypoxia were considered (Aim 2), as were studies investigating the effects of hypoxia on cognition (Aim 1).ResultsIn total, 18 studies met our inclusionary criteria for the systematic review, and 12 studies were meta-analyzed. Exposure to hypoxia impaired attentional ability (standardized mean difference (SMD) = –0.4), executive function (SMD = –0.18), and memory function (SMD = –0.26), but not information processing (SMD = 0.27). Aggregated results indicated that performing exercise under a hypoxia setting had a significant effect on cognitive improvement (SMD = 0.3, 95% confidence interval: 0.14 – 0.45, I² = 54%, p < 0.001). Various characteristics (e.g., age, cognitive task type, exercise type, exercise intensity, training type, and hypoxia level) moderated the effects of hypoxia and exercise on cognitive function.ConclusionExercise during exposure to hypoxia improves cognitive function. This association appears to be moderated by individual and exercise/hypoxia-related characteristics.     

The effect of wind on jumping distance in ski jumping – fairness assessed

The special wind compensation system recently adopted by Fédération Internationale de Ski (FIS; International Ski Federation) to consider the effects of changing wind conditions has caused some controversy. Here, the effect of wind on jumping distance in ski jumping was studied by means of computer simulation and compared with the wind compensation factors used by FIS during the World Cup season 2009/2010. The results showed clearly that the effect of increasing head/tail wind on jumping distance is not linear: +17.4 m/ ? 29.1 m, respectively, for a wind speed of 3 m/s. The linear formula used in the trial period of the wind compensation system was found to be appropriate only for a limited range of jumping distances as the gradient of the landing slope slows down the rate of distance change in long jumps.     

The effect of football boot upper padding on dribbling and passing performance using a test–retest validated protocol

Touch/control football boots are reportedly designed for optimal passing and dribbling. Little research exists on the effect of boot design on touch/control performance and no validated protocol has been developed for assessing passing and dribbling from an equipment focus. This study aimed to assess the effect of upper padding on dribbling and passing performance using a test–retest reliable test setup. Eight university players performed a protocol of dribbling, short and long passing in football boots with 0 and 6 mm of upper padding (Poron foam). The protocol was completed twice; the 0-mm padding results were used for test–retest validation, while the 0-mm versus 6-mm padding results were used to investigate the effect of padding. Dribbling performance was assessed though completion time, number of touches applied and lateral deviation from cones and passing performance through ball velocity and offset from target. The protocol demonstrated good test–retest reliability and indicated no significant differences in any of the 12 performance variables between the 0- and 6-mm padded boots. These findings suggest an element of design freedom in the use of padding within football boot uppers without affecting dribbling or passing performance.     

Are athletes on the right track? The effect of availability of an all-weather athletics track on athletics performance

In February of 2011, an earthquake destroyed the only all-weather athletics facility in the city of Christchurch, New Zealand. The all-weather track has yet to be replaced, and so since the loss of the track, local Christchurch athletes have only had a grass track for training and preparation for championship events. The present study considers what effect the loss of the training facility has had on the performance of athletes from Christchurch at national championship events. Not surprisingly, the study finds that there has been a deterioration in the performance in events that are heavily dependent upon the all-weather surface. However, somewhat more surprisingly, the loss of the track appears to have caused a significant improvement in the performance of Christchurch athletes in events that, while on the standard athletics programme, are not heavily dependent on track surface.     

Organisational culture in sport – A systematic review

The purpose of this paper was to systematically review the study of organisational culture in sport. The choice of research paradigms, methods, interests, perspectives, and definitions and operationalisation of organisational culture used in 33 studies was examined. This highlighted the variety of ways that culture has been studied in sport and the range of interests explored in the research, including informing athlete development, the link between the strength of culture and organisational performance and understanding the forces driving organisational diversity. Unlike the wider organisational culture literature, there has been a preference in sport to assume that culture was a variable to manipulate in an organisation. The opportunity to widen approaches to study organisational culture in sport is discussed, such as broadening the methods used to conduct studies, including both coaches and athletes in the population studied and using the fragmentation perspective, where ambiguity and conflict are considered in understanding culture.     

The effect of abusive leadership by coaches on Division I student-athletes’ performance: The moderating role of core self-evaluations

The aim of this study was to increase our understanding of the harm of abusive leadership on followers’ performance. Student-athletes (N = 145) at a US institution completed surveys. The authors used hierarchical regression analysis and an independent samples t-test to assess the hypotheses. Consistent with core self-evaluations theory, results revealed that core self-evaluations moderate the negative relationship between abusive leader behavior and student-athlete performance, such that the negative relationship is weakened for those with higher, rather than lower, levels of core self-evaluations. Results further indicated that women student-athletes are likely to have lower levels of core self-evaluations than are men, thus highlighting the potential increased impact that abusive leadership may have on women and their performance. Implications of these findings for research, theory and practice on abusive leadership and performance are discussed.     

The effect of equipment scaling on children’s sport performance: the case for tennis

The influence of scaling court-size and net height on children’s tennis performance was examined. Sixteen boys (9.7 ± 0.5 years) had to perform a 30-min match in four different conditions, where court-size and/or net height were scaled by using a scaling ratio based on the differences in temporal demands between the children and the adult game. These 30-min matches were analysed using Tennis Analyst (FairPlay Ltd., Jindalee, QLD, Australia) software to determine typical tennis match performance characteristics. Children hit more winners, more forced errors, played more volleys, struck more shots from a comfortable height and played in a more forward court position when the net was scaled. Scaling both the court and net lead to a faster children’s game, more closely approximating what is typical of the adult game. The differences between the typical tennis performance variables recorded suggested that scaling the net led to a more aggressive way of playing. Further, children enjoyed playing on the standard court–scaled net condition more than standard adult conditions. It is suggested that optimising the scaling of net height may be as critical as other task constraints, such as racquet length or court-size, as it leads to a more engaging learning environment for experienced children.     

The Governor has a sweet tooth – Mouth sensing of nutrients to enhance sports performance

Abstract

The oral–pharyngeal cavity and the gastrointestinal tract are richly endowed with receptors that respond to taste, temperature and to a wide range of specific nutrient and non-nutritive food components. Ingestion of carbohydrate-containing drinks has been shown to enhance endurance exercise performance, and these responses have been attributed to post-absorptive effects. It is increasingly recognised, though, that the response to ingested carbohydrate begins in the mouth via specific carbohydrate receptors and continues in the gut via the release of a range of hormones that influence substrate metabolism. Cold drinks can also enhance performance, especially in conditions of thermal stress, and part of the mechanism underlying this effect may be the response to cold fluids in the mouth. There is also some, albeit not entirely consistent, evidence for effects of caffeine, quinine, menthol and acetic acid on performance or other relevant effects. This review summarises current knowledge of responses to mouth sensing of temperature, carbohydrate and other food components, with the goal of assisting athletes to implement practical strategies that make best use of its effects. It also examines the evidence that oral intake of other nutrients or characteristics associated with food/fluid intake during exercise can enhance performance via communication between the mouth/gut and the brain.     

Influence of physical fitness on cognitive and academic performance in adolescents: A systematic review from 2005–2015

Background: The aim of this systematic review was to investigate the association of different components of physical fitness on cognitive performance (CP) and academic performance (AP) in adolescents, taking into account potential confounders. Method: Studies were identified in four databases (Pubmed, SportDiscus, Web of Science, and ProQuest) from January 2005 through to January 2015. A total of 21 articles met the inclusion criteria. Results: 8 studies showed association between physical fitness and CP, and 11 studies with AP. Cardiorespiratory fitness, speed-agility, motor coordination, and perceptual-motor skill are the highest measures associated with CP and AP. However, the findings on strength and flexibility are unclear. Finally, 62% of the 21 studies used confounders. The most controlled confounder were socioeconomic status, fatness, pubertal status, sex, and age. Conclusion: Fitness is associated with higher CP and AP. More research is needed in order to understand the causes of the differential effect of physical fitness components on CP and AP.     

Influence of a proprioceptive training on functional ankle stability in young speed skaters – a prospective randomised study

The influence of a 12-week-proprioceptive training on functional ankle stability was investigated in young speed skaters. Twenty-eight speed skaters were randomly divided into an intervention (n = 14) and into a control group (n = 14). A 15-min circle training was performed 5 times per week over a 12-week period. Measurements were taken prior to the training, after 6 and 12 weeks of training. Kinaesthesia was evaluated with the Isomed2000 in all movements of the ankle joint. Dynamic balance was tested with the Biodex Stability System at the stable level 8 and at the unstable level 2, measuring the overall stability index, the anterior/posterior and the medial/lateral scores. Static single-leg stance was evaluated using the Kistler force platform. Kinaesthesia of the intervention group improved significantly for plantarflexion of the right foot (P = 0.001) after 12 weeks. Dynamic balance showed significant differences in the intervention group after 12 weeks in comparison with the first measurement for each foot in the overall stability index, the anterior/posterior and the medial/lateral scores (P ≤ 0.017, respectively) at the unstable level 2. Functional ankle stability improved in terms of dynamic balance after 12 weeks of proprioceptive training. Therefore, inclusion of proprioceptive exercises in the daily training programme is recommended for young speed skaters.     

The impact of social influence on physical activity among adolescents – a longitudinal study

Abstract

Objectives: The purpose of the current study was to examine the impact of social support and negative social influence from various contexts on adolescents' current and intended physical activity (C&IPA) two years later. In addition, social influence related to C&IPA at baseline (16–17 years old) is compared to follow-up (18–19 years old). Methods: Questionnaire data was obtained from 404 students at the age of 16–17 and again at the age of 18–19. Relationships among variables were examined with structural equation modelling (SEM). Results: Social influence experienced by high-school students at 16–17 years of age had a direct suppressing effect and an indirect positive effect on their C&IPA two years later. Social support for physical activity was more complex and related to positive as well as negative relations at the age of 16–17 compared to two years later. Conclusions: The results imply that social support to adolescents should be offered over a longer period of time, with increased focus on its significance as a link from an initially external regulation to a more internal regulation of physical activity as students get older. Closer examination of maintaining, pro-activating and intervening effects of social support could enhance our understanding of direct and indirect effects of social support on physical activity.     

The effect of altering loading distance on skeleton start performance: Is higher pre-load velocity always beneficial?

Athletes initiating skeleton runs differ in the number of steps taken before loading the sled. We aimed to understand how experimentally modifying loading distance influenced sled velocity and overall start performance. Ten athletes (five elite, five talent; 67% of all national athletes) underwent two to four sessions, consisting of two dry-land push-starts in each of three conditions (preferred, long and short loading distances). A magnet encoder on the sled wheel provided velocity profiles and the overall performance measure (sled acceleration index). Longer pre-load distances (12% average increase from preferred to long distances) were related to higher pre-load velocity (r = 0.94), but lower load effectiveness (r = ?0.75; average reduction 29%). Performance evaluations across conditions revealed that elite athletes’ preferred distance push-starts were typically superior to the other conditions. Short loading distances were generally detrimental, whereas pushing the sled further improved some talent-squad athletes’ performance. Thus, an important trade-off between generating high pre-load velocity and loading effectively was revealed, which coaches should consider when encouraging athletes to load later. This novel intervention study conducted within a real-world training setting has demonstrated the scope to enhance push-start performance by altering loading distance, particularly in developing athletes with less extensive training experience.     

A systematic review of school-based physical activity interventions on children’s wellbeing

Purpose: The aim of this study was to review the effect of school-based physical activity interventions on children’s wellbeing.

Method: A systematic search of school-based physical activity studies was conducted using EBSCOhost PsycInfo, EBSCOhost Medline and Web of Science. Initially 995 studies were retrieved and, following the removal of duplicates, the titles and abstracts of 984 studies were screened. This screening identified 53 relevant studies from which 42 were excluded, resulting in 11 articles being reviewed.

Results: Three studies reported a positive increase in wellbeing; however, only one of those studies also significantly increased physical activity. It was apparent that the measurement of wellbeing and physical activity was inconsistent across studies, making conclusions difficult to draw. The wellbeing measures used neglected to account for the children’s perspectives of wellbeing.

Conclusions: The effect of a physical activity intervention on increasing wellbeing appears to be more complex than originally believed. The complexity may in part be due to methodological issues and the choice of wellbeing and physical activity measurement. We recommend that future physical activity interventions include a measure of wellbeing developed from the child’s perspective, and that future reviews narrow the search to only interventions that have had success at increasing physical activity before exploring effects on wellbeing.     

Understanding the effect of finger–ball friction on the handling performance of rugby balls

Handling errors are often seen in professional rugby games and even more so in amateur rugby. This paper analyses the problem of ball mishandling using high-speed video footage of passes and a bespoke finger friction rig. The high-speed video analysis showed that when the ball is caught, often there is a fluctuating movement of the fingers over the surface of the ball. It also showed that the fingers move over the surface of the ball when the ball is thrown, confirming that the dynamic friction is a good measure of how easily a ball can be handled. Rugby ball surface samples were used, on a finger friction rig, to assess the coefficient of friction between the finger and the balls. The currently manufactured balls displaying the highest coefficients of friction in clean, dry conditions were the design with square, ‘sharp’ pimples and also the design with a mixture of small and large pimples. The most consistent ball across wet and dry conditions was the ball with round, large, densely populated pimples. It was also shown that when water is added to the surface of the ball or finger, there was little variation in performance between the ball varieties.     

Effects of unsteady conditions on propulsion generated by the hand’s motion in swimming: a systematic review

The understanding of swimming propulsion is a key factor in the improvement of performance in this sport. Propulsive forces have been quantified under steady conditions since the 1970s, but actual swimming involves unsteady conditions. Thus, the purpose of the present article was to review the effects of unsteady conditions on swimming propulsion based on studies that have compared steady and unsteady conditions while exploring their methods, their limitations and their results, as well as encouraging new studies based on the findings of this systematic review. A multiple database search was performed, and only those studies that met all eligibility criteria were included. Six studies that compared steady and unsteady conditions using physical experiments or numerical simulations were selected. The selected studies verified the effects of one or more factors that characterise a condition as unsteady on the propulsive forces. Consequently, much research is necessary to understand the effect of each individual variable that characterises a condition as unsteady on swimming propulsion, as well as the effects of these variables as a whole on swimming propulsion.     

The influence of a 6.5% carbohydrate-electrolyte solution on performance of prolonged intermittent high-intensity running at 30°C

Nine male student games players consumed either flavoured water (0.1 g carbohydrate, Na⁺ 6 mmol · l^?1), a solution containing 6.5% carbohydrate-electrolytes (6.5 g carbohydrate, Na⁺ 21 mmol · l^?1) or a taste placebo (Na⁺ 2 mmol · l^?1) during an intermittent shuttle test performed on three separate occasions at an ambient temperature of 30°C (dry bulb). The test involved five 15-min sets of repeated cycles of walking and variable speed running, each separated by a 4-min rest (part A of the test), followed by 60 s run/60 s rest until exhaustion (part B of the test). The participants drank 6.5 ml · kg^?1 of fluid as a bolus just before exercise and thereafter 4.5 ml · kg^?1 during every exercise set and rest period (19 min). There was a trial order effect. The total distance completed by the participants was greater in trial 3 (8441 ± 873 m) than in trial 1 (6839 ± 512, P < 0.05). This represented a 19% improvement in exercise capacity. However, the trials were performed in a random counterbalanced order and the participants completed 8634 ± 653 m, 7786 ± 741 m and 7099 ± 647 m in the flavoured water (FW), placebo (P) and carbohydrate-electrolyte (CE) trials, respectively (P = 0.08). Sprint performance was not different between the trials but was impaired over time (FW vs P vs CE: set 1, 2.41 ± 0.02 vs 2.39 ± 0.03 vs 2.39 ± 0.03 s; end set, 2.46 ± 0.03 vs 2.47 ± 0.03 vs 2.47 ± 0.02 s; main

effect time, P < 0.01). The rate of rise in rectal temperature was greater in the carbohydrate-electrolyte trial (rise in rectal temperature/duration of trial, °C · h^?1; FW vs CE, P < 0.05; P vs CE, N.S.). Blood glucose concentrations were higher in the carbohydrate-electrolyte than in the other two trials (FW vs P vs CE: rest, 4.4 ± 0.1 vs 4.3 ± 0.1 vs 4.2 ± 0.1 mmol · l^?1; end of exercise, 5.4 ± 0.3 vs 6.4 ± 0.6 vs 7.2 ± 0.5 mmol · l^?1; main effect trial, P < 0.05; main effect time, P < 0.01). Plasma free fatty acid concentrations at the end of exercise were lower in the carbohydrate-electrolyte trial than in the other two trials (FW vs P vs CE: 0.57 ± 0.08 vs 0.53 ± 0.11 vs 0.29 ± 0.04 mmol · l^?1; interaction, P < 0.01). The correlation between the rate of rise in rectal temperature (°C · h^?1) and the distance completed was ?0.91, ?0.92 and ?0.96 in the flavoured water, placebo and carbohydrate-electrolyte conditions, respectively (P < 0.01). Heart rate, blood pressure, plasma ammonia, blood lactate, plasma volume and rate of perceived exertion were not different between the three fluid trials. Although drinking the carbohydrate-electrolyte solution induced greater metabolic changes than the flavoured water and placebo solutions, it is unlikely that in these unacclimated males carbohydrate availability was a limiting factor in the performance of intermittent running in hot environmental conditions.     

The effect of stress inoculation training on self‐reported stress,observer's rating of stress,heart rate and gymnastics performance

Eighteen volunteer female subjects received preliminary instruction in a simple gymnastics bench sequence. They were then given a pre‐intervention test on a bench at ground level. Self‐reported distress, an independent observer's ratings of distress and heart rates were monitored immediately prior to performance of the sequence. Performances were also videotaped and formally scored by a qualified gymnastics judge. Subjects were then randomly assigned to a stress inoculation training group or a ‘no stress management’ training control group. Stress inoculation group subjects then received seven sessions of training in relaxation, imagery and making self‐statements in order to develop a set of coping skills. Control group subjects also received seven training sessions during which they practised a series of coordination exercises, but no psychological stress management training was given to this group.

All subjects were then re‐tested on the bench sequence but this time at a height of 1.52 m. Self‐reported stress, observer's ratings of distress and heart rate were recorded as before. Performance was again videotaped for scoring. The stress inoculation group reported significantly less stress prior to the test on the elevated beam than the control group. However, the groups did not differ in terms of heart rate. Further, the stress inoculation group performed reliably better than the control group on the elevated bench.     

The effect of β-alanine supplementation on cycling time trials of different length

The varying results reported in response to β-alanine supplementation may be related to the duration and nature of the exercise protocol employed. We investigated the effects of β-alanine supplementation on a wide range of cycling performance tests in order to produce a clear concise set of criteria for its efficacy. Fourteen trained cyclists (Age?=?24.8?±?6.7?years; VO_2max?=?65.4?±?10.2 mL·kg·min^?1) participated in this placebo-controlled, double-blind study. Prior to supplementation, subjects completed two (familiarization and baseline) supramaximal cycling bouts until exhaustion (120% pre-supplementation VO_2max) and two 1-, 4- and 10-km cycling time trial (TT). Subjects then supplemented orally for 4 weeks with 6.4?g/d placebo or β-alanine and repeated the battery of performance tests. Blood lactate was measured pre-exercise, post-exercise and 5 min post-exercise. β-alanine supplementation elicited significant increases in time to exhaustion (TTE) (17.6?±?11.5 s; p?=?0.013, effect compared with placebo) and was likely to be beneficial to 4-km TT performance time (?7.8?±?8.1 s; 94% likelihood), despite not being statistically different (p?=?0.060). Performance times in the 1- and 10-km TT were not affected by treatment. For the highly trained cyclists in the current study, β-alanine supplementation significantly extended supramaximal cycling TTE and may have provided a worthwhile improvement to 4-km TT performance. However, 1- and 10-km cycling TT performance appears to be unaffected by β-alanine supplementation.