Evaluating the Validity of Tests to Predict Sprint and Change of Direction Speed in Para-Athletes With Brain Impairments.

Maximum running speed is a performance determinant in para-athletics and cerebral palsy football. Sixty international para-athletes with brain impairments completed five activity-limitation tests (standing broad jump, four bounds for distance, split jumps, 10-m speed skip, and running in place) and two criterion tests (40-m sprint and modified agility test). The same three tests (standing broad jump, four bounds for distance, and 10-m speed skip) that correlated with running performance in nondisabled runners (.67 < r < -.82; p < .05; 75% of variance) also correlated in para-athletes with brain impairments (.41 < r < -.62; p < .01; 55% of variance). Standing broad jump, four bounds for distance, split jumps, and running in place also correlated with change-of-direction speed (.43 < r < -.63; p < .01; 58% of variance). Results indicate that methods of classification for para-athletics with nondisabled runners are also valid with para-athletes with brain impairments, and new sport-specific relationships were found for assessing the performance of rapid and short sprints toward different directions, specific of a team para-sport like cerebral palsy football.

Longitudinal association of physical activity during pregnancy with maternal and infant outcomes: Findings from the Australian longitudinal study of women's health.

BACKGROUND: Physical activity has known benefits during pregnancy; however, the optimum volume of physical activity through the different stages of pregnancy is not well known. OBJECTIVES: The aims of this study were to investigate the associations of physical activity volume in pregnant women in each trimester of pregnancy with maternal and infant outcomes. DESIGN: The study involved 1657 pregnant women from the Australian Longitudinal Study on Women's Health, who completed surveys from 2006 to 2012 (aged 28-39 years). METHODS: Women reported being in either the first, second or third trimester of pregnancy. Women were grouped into four groups according to their self-reported physical activity during pregnancy: (1) Nil (0-<33.3 MET.min/week), (2) Low (33.3-<500 MET.min/week), (3) Moderate (500-<1000 MET.min/week) and (4) High (⩾1000 MET.min/week). Women who reported their physical activity during pregnancy completed a survey within three years after the birth, relating to outcomes associated with pregnancy and childbirth (gestational diabetes, hypertension, and antenatal depression and anxiety) and infant outcomes (birthweight and prematurity). RESULTS: There was no association of physical activity in any trimester with infant birthweight, prematurity, gestational diabetes, hypertension or antenatal depression. Antenatal anxiety was less prevalent in women who reported low (1.7%) or moderate (1.1%) physical activity than in those who reported no activity (4.7%; p = 0.01). CONCLUSION: Different amounts of physical activity during pregnancy were not associated with the measured adverse health outcomes. However, low and moderate amounts of physical activity were associated with reduced incidence of antenatal anxiety.

What are the odds? Identifying factors related to competitive success in powerlifting.

BACKGROUND: The ability for athletes to gain a competitive advantage over their opponents is well recognised. At times, this advantage may be considered a marginal gain. However, in the context of competition, marginal advantages may be the difference between winning and losing. This investigation explores how competition factors influence the odds of competitive success (i.e. winning) in powerlifting (PL) to assist athletes and coaches in achieving a competitive advantage. METHODS: A cross-sectional, retrospective analysis of competition data from raw/classic, Australian powerlifting competitions 2010-2019 was conducted. Data included 10,599 competition entries (males: n = 6567 [62%], females: n = 4032 [38%]). Independent t-tests were used to compare continuous data between sexes or winners and non-winners at an event. Cohen's d and the 95% confidence interval (d [95% CI]) were calculated. Univariate odds of winning an event based on independent variables (age [irrespective of category], sex, body weight and weight of first lift attempt [regardless of success]), were assessed by separate simple logistic regression. RESULTS: When compared to males, the odds of winning for females were 50% greater (OR [95% CI] 1.500 [1.384, 1.625]; P < 0.001). Athletes who had larger first lift attempts (Squat: + 7.0 kg P < 0.001, Bench Press: + 3.2 kg P < 0.001, and Deadlift: + 6.1 kg P < 0.001and competed for a longer period (winners: 401 vs non-winners: 304 days, P < 0.001) had an increased likelihood winning. Age was associated with increased odds of success for males (OR [95% CI] 1.014 [1.009, 1.019], P < 0.001) per additional year of age for males, but not females (P = 0.509). CONCLUSIONS: Multiple factors appear to contribute to the likelihood of winning a PL competition. These results may help coaches to develop competition and training strategies that optimise athletes' likelihood of competitive success in PL.

Impacts of squat attempt weight selection and success on powerlifting performance.

BACKGROUND: To date, there is no evidence to support the optimal competition strategy for success in powerlifting competitions. The purpose of this study was to analyze powerlifting (PL) competition data to assess the relationship between squat attempts, the success of each lift attempt, and weight increase between attempts, with winning. METHODS: The analysis from 'raw' Powerlifting Australia sanctioned competitions held between 2008 and 2019 included 10,672 individual competition entries (males: N.=6617, females: N.=4055). We reported Cohen's d, statistical significance, 95% confidence intervals and the univariate odds of winning an event. Factors were assessed by separate simple logistic regression and reported as an odds ratio. RESULTS: Overall, first squat attempt weight for those who won was on average 7.0 kg greater (P<0.001, d=0.14 [0.10, 0.18]) than for non-winners. In the total sample, athletes selected opening attempts which were an average of 92% of their achieved maximum on the day with 93.5% of competitors improving on this weight in subsequent attempts. Winners had a 0.5 kg (P<0.001, d=0.10 [0.06, 0.14]) greater absolute increase in weight between first and second lift attempts than non-winners. Overall, ~68% of winners successfully lifted their third attempt weight compared to ~64% of non-winners (P<0.001). CONCLUSIONS: A powerlifting athlete's odds of winning a competition overall are significantly increased by selecting a larger opening squat attempt weight than competitors and completing the attempt successfully. The opening squat may be one of the most important lifts during competition.

Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and exercise.

Chronic metabolic health diseases are increasing worldwide placing strain on healthcare systems and importantly, impacting individuals' quality of life. It is well established that many chronic diseases are associated with inflammation and oxidative stress. Exercise is a known strategy to manage and treat inflammation in animals and humans. Understanding the mechanisms which cause acute and chronic changes to systems via various exercise protocols may provide insights into how we can better clinically manage patients with inflammatory and oxidative stress associated diseases. Nrf2 is a basic leucine transcription factor which regulates the expression of antioxidant proteins to protect against damage caused by electrophilic or oxidative stress. The aim of this narrative review is to provide an overview of the literature which has investigated the relationship between acute and chronic exercise training and Nrf2 protein, mRNA and Nrf2-ARE binding activity. This narrative review presents analysis of twenty-nine articles presenting studies using animals and humans. Findings from animal models suggest that exercise increases all molecular aspects of the Nrf2-ARE pathway in all tissues studied. It was noted that there seems to be an age-related decline in Nrf2 protein upregulation with exercise training. In humans, however, there is a lack of evidence to support this claim.

Effect of Competition Frequency on Strength Performance of Powerlifting Athletes.

Pearson, J, Spathis, JG, van den Hoek, DJ, Owen, PJ, Weakley, J, and Latella, C. Effect of competition frequency on strength performance of powerlifting athletes. J Strength Cond Res 34(5): 1213-1219, 2020-Powerlifting (PL) requires athletes to achieve the highest possible "total" weight lifted across squat, bench press, and deadlift. Athletes compete multiple times per year; however, it is not well understood how often PL athletes should compete to facilitate maximal strength performance. This study investigated the effect of competition frequency on strength (relative and absolute) in PL athletes over a 12-month period. Results across all male (n = 563, mean ± SD; age; 28 ± 10 years, body mass; 89.3 ± 19.3 kg) and female (n = 437, age; 31 ± 11 years, body mass; 70.1 ± 15.8 kg) PL athletes were collated. Total competition scores were used to calculate absolute and relative strength for each competition. Linear mixed models with random effects, and effect sizes ± 95% confidence intervals compared competition frequency and total score for (a) all, (b) male, and (c) female competition entries, respectively. The association between total score at each competition was assessed with Pearson's correlation coefficient for the same independent variables. Results demonstrate greater absolute strength at competition 2 for all athletes (5.1%: p = 0.043: d = 0.16) and males (2.9%: p = 0.049: d = 0.15). For females, absolute strength was greater at competition 5 compared to 1 (12.0%: p = 0.001: d = 0.65) and 2 (9.6%: p = 0.007: d = 0.50). Weak positive correlations for relative strength and number of times competed for males were evident between competitions 1 to 4 (r = 0.070-0.085, p = 0.003-0.043). For females, 3 competitions weakly correlated with absolute strength (r = 0.106, p = 0.016). PL athletes who compete multiple times per year are more likely to achieve higher totals; however, there is an upper limit to the number of competitions (4 per year) that seem to allow a performance increase.

Guidelines for the delivery and monitoring of high intensity interval training in clinical populations.

High intensity interval training (HIIT) is now recognized in international clinical-based exercise guidelines as an appropriate and beneficial adjunct to moderate intensity continuous training. HIIT involves alternating periods of high intensity aerobic exercise with light recovery exercise or no exercise, allowing for greater physiological stimulus and adaptation than moderate intensity continuous training (MICT) for cardiorespiratory fitness and other cardiometabolic processes. However, there is no universal criteria or framework for the prescription and monitoring of HIIT in clinical populations, and safety concerns remain a common barrier for implementing HIIT as standard care. Historically, exercise intensity has been prescribed using heart rate (HR) targets derived from either a predicted maximal HR (HRmax) or from an attempt to objectively measure HRmax. However, using this approach alone has a number of limitations. Here we provide guidelines to improve the delivery of HIIT in cardiometabolic populations using 1) a framework for HIIT prescription using a combination of objective and subjective measures of exercise intensity, and 2) clinical considerations for assessment and monitoring to maximize patient safety. The framework involves an individualized step-by-step process to calculate, validate, and calibrate HR target zones for HIIT training to allow for appropriate workload prescription and progression. We strongly recommend this framework be used in future clinical trials investigating HIIT.

Establishing the reliability of a novel battery of range of motion tests to enable evidence-based classification in Para Swimming.

OBJECTIVES: To evaluate the reliability of swimming-specific range of movement tests developed in order to permit evidenced-based classification in the sport of para swimming. DESIGN: Test-retest intra- and inter-examiner reliability. SETTING: International Swimming training camps and university exercise science departments. PARTICIPANTS: 42 non-disabled participants (mean age 23.2 years) and 24 Para swimmers (mean age 28.5 years). MAIN OUTCOME MEASURES: Intra- and inter-examiner reliability of a battery of novel active range of motion tests. RESULTS: Good to excellent intra-examiner reliability was found for the majority (32/34) of tests in non-disabled participants (ICC = 0.85-0.98). SEM values ranged from 1.18° to 6.11°. Similarly, good to excellent inter-examiner reliability was found for the majority (35/42) of tests in non-disabled participants (ICC = 0.85-0.98). SEM values range from 0.73° to 6.52°. Para swimmers exhibited significantly reduced range of motion compared to non-disabled participants. CONCLUSIONS: The large majority of ROM tests included in this novel battery were reliable both within and between examiners in non-disabled participants. The tests were found to differentiate between non-disabled participants and Para swimmers with hypertonia or impaired muscle power.