A Descriptive Case Study of Skilled Football Goalkeepers During 1 v 1 Dyads: A Case for Adaptive Variability in the Quiet Eye.

Evidence investigating skilled performers in sport suggests that a prominent component of skilled behavior is, in part, due to the development of more effective and efficient perception-action couplings. Further, the Quiet Eye has emerged as a useful tool in which to investigate how skilled performers regulate action through fixating on visual information within the immediate environment before the onset of a goal directed movement. However, only a few contributions to the literature have attempted to examine the individual variations within these Quiet Eye fixations in skilled participants. In this case study, we first asked how goalkeepers control their actions, via the Quiet Eye in a representative task. Second, we sought to examine whether inter- and intra- individual differences in the Quiet Eye are present in skilled goalkeepers as a functional component of skilled performance. Results were consistent with previous work on football goalkeepers, with QE fixations located at the ball and visual pivot. However, individual analysis reveals different Quiet Eye gaze patterning between (inter) and within (intra) the goalkeepers during saving actions. To conclude, we have provided a descriptive case study in attempt to understand the Quiet Eye behaviors of a skilled sample of professional goalkeepers. In doing so we have suggested how adaptive variability, founded upon an Ecological Dynamics framework, may provide further insight into the function of the Quiet Eye.

Physical Activity, Mental Health and Wellbeing of Adults within and during the Easing of COVID-19 Restrictions, in the United Kingdom and New Zealand.

Physical activity (PA) participation was substantially reduced at the start of the COVID-19 pandemic. The purpose of this study was to assess the association between PA, mental health, and wellbeing during and following the easing of COVID-19 restrictions in the United Kingdom (UK) and New Zealand (NZ). In this study, 3363 adults completed online surveys within 2-6 weeks of initial COVID-19 restrictions (April/May 2020) and once restrictions to human movement had been eased. Outcome measures included the International Physical Activity Questionnaire Short-Form, Depression Anxiety and Stress Scale-9 (mental health) and World Health Organisation-5 Wellbeing Index. There were no differences in PA, mental health or wellbeing between timepoints (p > 0.05). Individuals engaging in moderate or high volume of PA had significantly better mental health (-1.1 and -1.7 units, respectively) and wellbeing (11.4 and 18.6 units, respectively) than individuals who engaged in low PA (p < 0.001). Mental health was better once COVID-19 restrictions were eased (p < 0.001). NZ had better mental health and wellbeing than the UK (p < 0.001). Participation in moderate-to-high volumes of PA was associated with better mental health and wellbeing, both during and following periods of COVID-19 containment, compared to participation in low volumes of PA. Where applicable, during the current or future pandemic(s), moderate-to-high volumes of PA should be encouraged.

The Impact of a Repeated Sprint Training Program on Performance Measures in Male Field Hockey Players.

ABSTRACT: Taylor, L and Jakeman, JR. The impact of a repeated sprint training program on performance measures in male field hockey players. J Strength Cond Res 36(7): 1984-1988, 2022-Sprint interval training (SIT) has been shown to be effective at improving athletic performance in laboratory studies, but the efficacy of SIT programs incorporated into normal training schedules is poorly considered. This study aimed to investigate the impact of a running SIT intervention applied to competitive athletes within a training program and to consider whether an uphill or flat (horizontal) SIT protocol had different effects on performance changes over time. Eighteen male hockey players (mean ± SD: age, 20.7 ± 0.9 years; hockey training experience, 9.9 ± 3.0 years) completed 2 sessions of SIT per week for 8 weeks, with intensity progressively increasing from 6 sprints in week 1 to 12 sprints in week 8. Subjects were randomly allocated to a flat or uphill (6% gradient) training condition (n = 9) and completed 30-m maximal sprint efforts with a 30-second recovery. Performance measures, including squat jump, 30-m sprint speed, and repeated sprint time, all improved significantly (p ≤ 0.05). Squat jump performance improved by 3.84 (d = 0.8) and 3.55 (d = 0.7) in the flat and uphill groups, respectively. Thirty-meter sprint speed improved by 0.06 (d = -0.4) and 0.10 (d = -0.7), and repeated sprint performance also improved, with the fastest of recorded sprints after intervention being 0.06 and 0.04 faster in the flat and uphill groups, respectively. Supplementing a normal hockey training week with SIT can have a positive impact on performance measures in male university hockey players. Furthermore, using an uphill training modality had a small, nonsignificant additional positive effect to some performance adaptations.

Physical activity, mental health and well-being of adults during initial COVID-19 containment strategies: A multi-country cross-sectional analysis.

OBJECTIVES: To assess physical activity (PA), mental health and well-being of adults in the United Kingdom (UK), Ireland, New Zealand and Australia during the initial stages of National governments' Coronavirus disease (COVID-19) containment responses. DESIGN: Observational, cross-sectional. METHODS: An online survey was disseminated to adults (n=8,425; 44.5±14.8y) residing in the UK, Ireland, New Zealand and Australia within the first 2-6 weeks of government-mandated COVID-19 restrictions. Main outcome measures included: Stages of Change scale for exercise behaviour change; International Physical Activity Questionnaire (short-form); World Health Organisation-5 Well-being Index; and the Depression Anxiety and Stress Scale-9. RESULTS: Participants who reported a negative change in exercise behaviour from before initial COVID-19 restrictions to during the initial COVID-19 restrictions demonstrated poorer mental health and well-being compared to those demonstrating either a positive-or no change in their exercise behaviour (p<0.001). Whilst women reported more positive changes in exercise behaviour, young people (18-29y) reported more negative changes (both p<0.001). Individuals who had more positive exercise behaviours reported better mental health and well-being (p<0.001). Although there were no differences in PA between countries, individuals in New Zealand reported better mental health and well-being (p<0.001). CONCLUSION: The initial COVID-19 restrictions have differentially impacted upon PA habits of individuals based upon their age and sex, and therefore have important implications for international policy and guideline recommendations. Public health interventions that encourage PA should target specific groups (e.g., men, young adults) who are most vulnerable to the negative effects of physical distancing and/or self-isolation.

Comparison of a Countermovement Jump Test and Submaximal Run Test to Quantify the Sensitivity for Detecting Practically Important Changes Within High-Performance Australian Rules Football.

PURPOSE: To determine the typical variation of variables from a countermovement jump (CMJ) test and a submaximal run test (SRT), along with comparing the sensitivity of each test for the detection of practically important changes within high-performance Australian rules football players. METHODS: A total of 23 professional and semiprofessional Australian rules football players performed 6 CMJs and three 8-second 50-m runs every 30 seconds (SRT), 7 days apart. Absolute and trial-to-trial reliability was represented as a coefficient of variation, CV (±90% confidence intervals). Test-retest reliability was examined using the magnitude of the difference (effect size [±90% confidence interval]) from week 1 to week 2. The smallest worthwhile change was calculated as 0.25 × SD. RESULTS: Good reliability (CVs = 6.6%-9.3%) was determined for all variables except eccentric displacement (CV = 12.8%), with no clear changes observed in any variables between week 1 and week 2. All variables from the SRT possessed a CV less than smallest worthwhile change, indicating an ability to detect practically important changes in performance. Only peak velocity from the CMJ test possessed a CV less than smallest worthwhile change, exhibiting a limitation of this test in detecting practically meaningful changes within this environment. CONCLUSIONS: The results suggest that while all variables possess acceptable reliability, a SRT might offer to be a more sensitive monitoring tool than a CMJ test within high-performance Australian rules football, due to its greater ability for detecting practically important changes in performance.

Effect of Work: Rest Ratio on Cycling Performance Following Sprint Interval Training: A Randomized Control Trial.

Lloyd Jones, MC, Morris, MG, and Jakeman, JR. Effect of work: Rest ratio on cycling performance following sprint interval training: A randomized control trial. J Strength Cond Res 33(12): 3263-3268, 2019-Sprint interval training (SIT) has been shown to improve performance measures in a range of individuals, and it is understood that different responses can be elicited from different training protocols. However, consideration of changes in work to rest ratios could offer important insight into optimizing training programs. The purpose of this study was to investigate the effect of 3 different work to rest ratios on exercise performance. Thirty-six male and female subjects were randomly allocated to 1 of 3 training groups or a nontraining control group. Training consisted of 10 × 6 second "all-out" sprints on a cycle ergometer, with a 1:8, 1:10, or 1:12 work-to-rest ratio. Performance data, including peak power output, performance decrement, and 10-km time trial performance data were collected before and after 2 weeks of SIT. There were significant (p ≤ 0.05) improvements in all parameters for the training groups, but no changes were observed in the control condition. Peak power increased by 57.2, 50.7, and 53.7 W in the 1:8, 1:10 and 1:12 groups, respectively, with no significant differences in response between conditions. Time trial performance improved significantly in all 3 training conditions (29.4, 8.7, and 25.1 seconds in the 1:8, 1:10, and 1:12 groups), while worsening in the control group. All training conditions resulted in significant improvements in performance, but there were no significant differences in improvement for any of the groups. Any of the 3 stated that work to rest ratios would be appropriate for use with athletes and allow some level of personal preference for those interested in using the protocol.

The effects of fatigue on the running profile of elite team sport athletes. A systematic review and meta-analysis.

INTRODUCTION: With the underlying mechanisms of fatigue shown to be task-specific, gaining an understanding of changes within the running profile due to fatigue may provide a greater task-specific method for monitoring neuromuscular fatigue (NMF) in elite team sport athletes. This review aimed to identify, review and summarize the literature to understand the effects of fatigue on the running profile of elite team sport athletes. EVIDENCE ACQUISITION: MEDLINE, SPORTDiscus, EMBASE and CINAHL were searched. To manage heterogeneity in athlete characteristics and sport demands, studies were limited to elite male field/court team sports, in which changes in running, gait or stride characteristics were assessed. EVIDENCE SYNTHESIS: Thirteen studies were included in the analysis with changes in sprint time, kinematic variables; contact time, center of mass vertical displacement and vertical stiffness, GPS accelerometer vector variables; z and y, and mechanical parameters; velocity and V0, all shown to be sensitive measures of fatigue. Due to having at least three sets of data points, meta-analysis was run for sprint time, with results showing a significant increase immediately postexercise (effect size [ES]±95% confidence interval [CI]; 1.67±1.61, P=0.04), but no change 24 hours postexercise (ES±95% CI; 0.93±3.21, P=0.57). CONCLUSIONS: The findings indicate that fatigue has a negative impact on the running profile in elite team sport athletes, offering an alternative task-specific measure of monitoring NMF in this population. However, due to large discrepancies in protocols, future research is required to allow greater uniformity in variables and methods.

A Novel Method of Assessment for Monitoring Neuromuscular Fatigue in Australian Rules Football Players.

Purpose: To compare the sensitivity of a submaximal run test (SRT) with a countermovement-jump test (CMJ) to provide an alternative method of measuring neuromuscular fatigue (NMF) in high-performance sport. Methods: A total of 23 professional and semiprofessional Australian rules football players performed an SRT and CMJ test prematch and 48 and 96 h postmatch. Variables from accelerometers recorded during the SRT were player load 1D up (vertical vector), player load 1D side (mediolateral vector), and player load 1D forward (anteroposterior vector). Meaningful difference was examined through magnitude-based inferences (effect size [ES]), with reliability assessed as typical error of measurements expressed as coefficient of variance. Results: A small decrease in CMJ height, ES -0.43 ± 0.39 (likely), was observed 48 h postmatch before returning to baseline 96 h postmatch. This was accompanied by corresponding moderate decreases in the SRT variables player load 1D up, ES -0.60 ± 0.51 (likely), and player load 1D side, ES -0.74 ± 0.57 (likely), 48 h postmatch before also returning to prematch baseline. Conclusion: The results suggest that in the presence of NMF, players use an alternative running profile to produce the same external output (ie, time). This indicates that changes in accelerometer variables during an SRT can be used as an alternative method of measuring NMF in high-performance Australian rules football and provides a flexible option for monitoring changes in the recovery phase postmatch.

Early Adaptations to a Two-Week Uphill Run Sprint Interval Training and Cycle Sprint Interval Training.

This study sought to compare early physiological and performance adaptations between a two-week cycle sprint interval training (SIT) and uphill run sprint training (UST) programs. Seventeen recreationally active adult males (age = 28 ± 5 years; body mass (BM) = 78 ± 9 kg) were assigned to either a control (n = 5), SIT (n = 6), or UST (n = 6) group. A discrete group of participants (n = 6, age = 33 ± 6 years, and body mass = 80 ± 9 kg) completed both training protocols to determine acute physiological responses. Intervention groups completed either a run or cycle peak oxygen uptake (VO2peak) test (intervention type dependent) prior to and following two weeks of training. Training comprised of three sessions per week of 4 × 30-s "all-out" sprints with a four-minute active recovery between bouts on a cycle ergometer against 7.5% of body mass in the SIT group and on a 10% slope in the UST group. The VO2peak values remained unchanged in both training groups, but time-to-exhaustion (TTE) was significantly increased only in the UST group (pre-495 ± 40 s, post-551 ± 15 s; p = 0.014) and not in the SIT group (pre-613 ± 130 s, post-634 ± 118 s, p = 0.07). Ventilatory threshold (VT) was significantly increased in both training groups (SIT group: pre-1.94 ± 0.45 L·min-1, post-2.23 ± 0.42 L·min-1; p < 0.005, UST group: pre-2.04 ± 0.40 L·min-1, post-2.33 ± 0.34 L·min-1, p < 0.005). These results indicate that UST may be an effective alternative to SIT in healthy individuals.

Impact of time and work:rest ratio matched sprint interval training programmes on performance: A randomised controlled trial.

OBJECTIVES: The aim of this study was to examine the effects of a short training intervention using two repeated sprint protocols matched for total sprint duration and work:rest ratio. DESIGN: Randomised-controlled trial. METHODS: Thirty physically active males were randomly allocated to one of two sprint training groups: a 6s group, a 30s group or a non-exercising control. The training groups were matched for work:rest ratio and total sprint time per session, and completed 6 training sessions over a 2-week period. Before and after the 2 week training period, participants completed a VO2max test and a 10km time trial on a cycle ergometer. RESULTS: Time trial performance increased significantly by 5.1% in 6s (630±115s to 598±92s; p<0.05) and 6.2% in 30s (579±68s to 543±85s; p<0.05) from baseline testing, but there was no significant change in the control group (p>0.05), and no significant difference between exercise groups (p>0.05). The 6s group increased peak power output by 9.0% (from 1092±263W to 1181±248W; p<0.05) from sprint session 1 to 6, and the 30s group by 20.0% (1041±161W to 1237±159W; p<0.05). CONCLUSIONS: This study indicates that both 6 and 30s bouts of repeated sprint exercise, matched for total sprint duration and W:R can improve athletic performance.

Efficacy of a Four-Week Uphill Sprint Training Intervention in Field Hockey Players.

Jakeman, JR, McMullan, J, and Babraj, JA. Efficacy of a four-week uphill sprint training intervention in field hockey players. J Strength Cond Res 30(10): 2761-2766, 2016-Current evidence increasingly suggests that very short, supramaximal bouts of exercise can have significant health and performance benefits. Most research conducted in the area, however, uses laboratory-based protocols, which can lack ecological validity. The purpose of this study was to examine the effects of a high-intensity sprint training program on hockey-related performance measures. Fourteen semiprofessional hockey players either completed a 4-week high-intensity training (HIT) intervention, consisting of a total of 6 sessions of HIT, which progressively increased in volume (n = 7), or followed their normal training program (Con; n = 7). Straight-line sprint speed, with and without a hockey stick and ball, and slalom sprint speed, with and without a hockey stick and ball, were used as performance indicators. Maximal sprint speed over 22.9 m was also assessed. On completion of the 4-week intervention, straight-line sprint speed improved significantly in the HIT group (∼3%), with no changes in performance for the Con group. Slalom sprint speed, both with and without a hockey ball, was not significantly different after the training program in either group. Maximal sprint speed improved significantly (12.1%) in the HIT group, but there was no significant performance change in the Con group. The findings of this study indicate that a short period of HIT can significantly improve hockey-related performance measures and could be beneficial to athletes and coaches in field settings.

Effect of lower-limb compression clothing on 400-m sprint performance.

This study investigated the effects of wearing a variety of lower-limb compression garments on 400-m sprint performance. Eleven 400-m male runners (23.7 ± 5.7 years, 1.78 ± 0.08 m, and 75.3 ± 10.0 kg) completed six, 400-m running tests on an outdoor, all-weather running track on separate occasions. The participants completed 2 runs with long-length lower-limb compression garments (LG; hip-to-ankle), a combination of short-length lower-limb compression garments (SG; hip-to-knee) with calf compression sleeves (ankle-to-knee), or without compression garments (CON; shorts), in a randomized, counterbalanced order. Overall lap time and 100-m split times, heart rate, and ratings of perceived exertion (RPEs) were measured during the 400-m run. Blood lactate concentration, visual analogue scales for perceived soreness, feeling and arousal, and scales for perceived comfort and tightness when wearing compression garments, were assessed before (preexercise, post-warm-up) and after 400-m performance (post, 4 minutes postexercise, after a warm-down). Statistical analysis revealed no differences between conditions in overall 400-m performance, 100-m split times, or blood lactate concentration (p > 0.05), although there was a trend for an increased rate of blood lactate clearance when wearing compression garments. A significantly lower RPE (p > 0.05) was however observed during LG (13.8 ± 0.9) and SG (13.4 ± 1.1) when compared with CON (14.0 ± 1.0). This study has demonstrated that lower-limb compression garments may lower the effort perception associated with 400-m performance, despite there being no differences in overall athletic performance.

Extremely short duration high-intensity training substantially improves endurance performance in triathletes.

High-intensity training (HIT) involving 30-s sprints is an effective training regimen to improve aerobic performance. We tested whether 6-s HITs can improve aerobic performance in triathletes. Six subelite triathletes (age, 40 ± 9 years; weight, 86 ± 11 kg; body mass index, 26 ± 3 kg·m⁻²) took part in cycle HIT and 6 endurance-trained subelite athletes (age, 36 ± 9 years; weight, 82 ± 11 kg; BMI, 26 ± 3 kg·m⁻²) maintained their normal training routine. Before and after 2 weeks of HIT, involving 10 × 6-s sprints or normal activity, participants performed a self-paced 10-km time trial and a time to exhaustion test on a cycle ergometer. Finger prick blood samples were taken throughout the time to exhaustion test to determine blood lactate concentration. Two weeks of HIT resulted in a 10% decrease in self-paced 10-km time trial (p = 0.03) but no significant change in time to exhaustion. The time taken to reach onset of blood lactate accumulation (OBLA, defined as the point where blood lactate reaches 4 mmol·L⁻¹) was significantly increased following 2 weeks of HIT (p = 0.003). The change in time trial performance was correlated to the change in time taken to reach OBLA (R² = 0.63; p = 0.001). We concluded that a very short duration HIT is a very effective training regimen to improve aerobic performance in subelite triathletes and this is associated with a delay in blood lactate build-up.

Efficacy of lower limb compression and combined treatment of manual massage and lower limb compression on symptoms of exercise-induced muscle damage in women.

Strategies to manage the symptoms of exercise-induced muscle damage (EIMD) are widespread, though are often based on anecdotal evidence. The aim of this study was to determine the efficacy of a combination of manual massage and compressive clothing and compressive clothing individually as recovery strategies after muscle damage. Thirty-two female volunteers completed 100 plyometric drop jumps and were randomly assigned to a passive recovery (n = 17), combined treatment (n = 7), or compression treatment group (n = 8). Indices of muscle damage (perceived soreness, creatine kinase activity, isokinetic muscle strength, squat jump, and countermovement jump performance) were assessed immediately before and after 1, 24, 48, 72, and 96 hours of plyometric exercise. The compression treatment group wore compressive tights for 12 hours after damage and the combined treatment group received a 30-minute massage immediately after damaging exercise and wore compression stockings for the following 11.5 hours. Plyometric exercise had a significant effect on all indices of muscle damage (p < 0.05). The treatments significantly reduced decrements in isokinetic muscle strength, squat jump performance, and countermovement jump performance and reduced the level of perceived soreness in comparison with the passive recovery group (p < 0.05). The addition of sports massage to compression after muscle damage did not improve performance recovery, with recovery trends being similar in both treatment groups. The treatment combination of massage and compression significantly moderated perceived soreness at 48 and 72 hours after plyometric exercise (p < 0.05) in comparison with the passive recovery or compression alone treatment. The results indicate that the use of lower limb compression and a combined treatment of manual massage with lower limb compression are effective recovery strategies following EIMD. Minimal performance differences between treatments were observed, although the combination treatment may be beneficial in controlling perceived soreness.

Lower limb compression garment improves recovery from exercise-induced muscle damage in young, active females.

This study aimed to investigate the efficacy of lower limb compression as a recovery strategy following exercise-induced muscle damage (EIMD). Seventeen female volunteers completed 10 x 10 plyometric drop jumps from a 0.6-m box to induce muscle damage. Participants were randomly allocated to a passive recovery (n = 9) or a compression treatment (n = 8) group. Treatment group volunteers wore full leg compression stockings for 12 h immediately following damaging exercise. Passive recovery group participants had no intervention. Indirect indices of muscle damage (muscle soreness, creatine kinase activity, knee extensor concentric strength, and vertical jump performance) were assessed prior to and 1, 24, 48, 72, and 96 h following plyometric exercise. Plyometric exercise had a significant effect (p < or = 0.05) on all indices of muscle damage. The compression treatment reduced decrements in countermovement jump performance (passive recovery 88.1 +/- 2.8% vs. treatment 95.2 +/- 2.9% of pre-exercise), squat jump performance (82.3 +/- 1.9% vs. 94.5 +/- 2%), and knee extensor strength loss (81.6 +/- 3% vs. 93 +/- 3.2%), and reduced muscle soreness (4.0 +/- 0.23 vs. 2.4 +/- 0.24), but had no significant effect on creatine kinase activity. The results indicate that compression clothing is an effective recovery strategy following exercise-induced muscle damage.