The primary aim of this study was to investigate the acute dose response of 4 different individualized high intensity interval training (HIIT) prescriptions on upright standing postural control. Further, due to the similarity between the factors contributing to the change in postural control and fatiguability, the secondary aim of this study was to evaluate the correlation between upright standing postural control and parameters of performance [electromyographic fatigue threshold (EMG_FT)] and perceived fatiguability [rate of perceived exertion (RPE), motivation, muscle soreness] in endurance athletes.

For this purpose, a sample of 40 trained endurance athletes (age: 21.47 ± 2.61 years; height: 164.77 ± 7.3 cm; weight: 57.53 ± 6.3 kg; BMI: 21.18 ± 7.4 kg/m²) was recruited for the study and randomly allocated into 4 groups. After assessing the demographic, physiological [height, weight, heart rate, blood pressure, maximal oxygen consumption (VO_2max), velocity at onset of blood lactate accumulation (vOBLA)] and fatigability parameters, different groups were assigned individualized HIIT sessions with varied recovery interval intensity and duration in between the pre- and post-postural control assessments.

All HIIT protocols caused a significant increment in the postural sway in all four directions (front, back, left, and right) which was not significantly different from each other. A strong negative correlation between the change in postural control was reported with VO_2max, EMG_FT and a strong positive correlation with height, weight, body mass index, RPE, while the correlation coefficient revealed a moderate positive correlation with vOBLA.

This study concludes that all the four HIIT prescriptions have similar acute effect on the upright standing postural control and it is strongly correlated with fatiguability.

Athletes have presented a deficiency in relative energy in recent years, which calls for appropriate nutritional guidance based on the estimated energy requirement (EER)—the target amount of daily energy intake (EI). The calculation of EER requires longitudinal physical activity level (PAL) data, which has received insufficient attention. Therefore, this study aimed to clarify the changes in PAL by training periodization using the doubly labeled water (DLW) method, combined with the current status of EI by competition characteristics.

The participants comprised four male sprint athletes and five male endurance athletes at the national level. The experimental periods were normal training (NT) and tapering training (TT) periods. PAL was measured using the DLW method, and EI was measured by the dietary record method.

PAL of the sprint athletes in the NT periods was significantly higher than in TT periods. EI had no significant differences between the two periods. PAL and EI of the endurance athletes had no significant differences beteen the two periods.

These findings indicated that in sprint athletes, different PAL was observed between the two periods, with the TT period suggesting a lower value than the NT period. In endurance athletes, it had similar PAL values between the two periods. This suggests that the degree of influence of the training period on PAL may vary depending on the athletic events. Furthermore, the EI was not adjusted for changes in PAL, and the participants observed the status of energy-deficient regardless of discipline or training period.

Thoroughbred racing jockeys compete at maximum physiological capacity in a sport with a high risk of falls and injury. A greater understanding of the physical capacities determining jockey performance may lead to minimum physical performance parameters and corrective interventions to improve jockey fitness and performance and reduce jockey and horse injury. The aim of this study was to develop appropriate physical testing procedures for jockeys and a physical fitness profile for different licence levels.

Fifty-eight jockeys (n = 24 females, n = 34 males), representing all apprentice jockeys licenced in New Zealand in 2021 (100%, n = 8 probationers and n = 39 apprentices) and eleven professional jockeys (14%) were assessed to determine baseline physiological and fitness data. Descriptive statistics and boxplots were used to compare aerobic fitness, abdominal (core), upper and lower body strength, muscular power, reaction time, flexibility and a novel ‘saddle’ test targeting lower body strength, balance, and endurance between licencing levels. Effect Size (ES) was used to determine magnitude of differences between groups.

More experienced jockeys had greater relative lower body strength (ES = 0.2–0.7) and better balance (ES = 0.5–0.9) compared to the less experienced groups. Jockeys who were in the top 20 of the premiership table (jockey rankings) had faster reaction times (ES = 0.7) and greater core extensor strength (ES = 0.7) than other cohorts. Most tests showed little differentiation between jockey licence levels, however the ‘saddle test’ showed greater variability in the less experienced race riders. This test may be an effective measure of jockey baseline performance.

These data could be used to inform minimum jockey licencing requirements and future physical fitness training programmes to increase jockey physiological fitness, thereby minimising risk of falls or injury due to physiological deficits and performance.

The purpose of this study was to compare in-game external load demands from the previous game format (two, 30-min halves) to the new format (four, 15-min quarters) in collegiate women’s lacrosse.

External workload variables (total distance, high-intensity distance [HID], sprints, sprint distance, accelerations, and decelerations) were collected via microtechnology per minute of athlete (n = 13) playing time by half (H) for year one (Y1) and by quarter (Q) for year 2 (Y2).

In H1, Y2 registered more distance (Y2: 179 ± 37 m/min, Y1: 69 ± 45 m/min), HID (Y2: 26.4 ± 9.8 m/min, Y1: 6.5 ± 5.0 m/min), accelerations (Y2: 3.2 ± 0.8 reps/min, Y1: 1.4 ± 0.9 reps/min), decelerations (Y2: 1.0 ± 0.3 reps/min, Y2: 0.4 ± 0.3 reps/min, all P < 0.001), sprints (Y2: 0.36 ± 0.25 reps/min, Y1: 0.07 ± 0.06 reps/min, P = 0.006) and sprint distance (Y2: 13.2 ± 8.7 m/min, Y1: 2.3 ± 2.0 m/min, P = 0.004). Y2 was greater in H2 for distance (Y2: 175 ± 24 m/min, Y1: 109 ± 28 m/min, P < 0.001), HID (Y2: 21.1 ± 0.6 m/min, Y1: 9.9 ± 3.3 m/min, P < 0.001), sprints (Y2: 0.29 ± 0.19 reps/min, Y1: 0.11 ± 0.04 reps/min, P = 0.003), accelerations (Y2: 2.8 ± 0.6 reps/min, Y1: 2.1 ± 0.5 reps/min, P = 0.003), decelerations (Y2: 0.9 ± 0.2 reps/min, Y1: 0.5 ± 0.1 reps/min, P = 0.001) and sprint distance (Y2: 10.6 ± 6.4 m/min, Y1: 3.7 ± 1.4 m/min, P = 0.002). Differences in whole game was found for sprints (Y2: 0.24 ± 0.3 reps/min, Y1: 0.11 ± 0.05 reps/min, P = 0.009).

The new competitive format presented a greater demand for players, with more high-intensity efforts and greater anaerobic demand. Coaches can use this information as key performance indicators to develop and alter training to focus on meeting higher-intensity game demands.

Examine for injury risk factors and establish clinical cut-off values related to size and function of trunk muscles.

A prospective study of 28 professional Rugby League players was conducted. Cross-sectional areas (CSAs) of the multifidus (MF), quadratus lumborum (QL) and ability to contract the abdominal and MF muscles were measured from pre-season ultrasound images. Playing season injuries resulting in games missed were recorded by club personnel. Logistic regression models were used to determine the adjusted odds ratios for trunk muscle measures as risk factors for playing season injuries.

The adjusted odds ratio (OR) values indicated that if a player had a small MF muscle (< 9.98 cm² at L5; P = 0.032) or a small QL (< 10.8 cm²; P = 0.045), their odds of more games missed due to season injuries was increased (OR MF = 9.4; 95% CI = 1.21–72.9; OR QL = 7.3; 95% CI = 1.1–51.6). For players with increased contraction of the MF (contraction > 7.2%; P = 0.028) and abdominal muscles (> 49.9%; P = 0.08), the odds of sustaining a concussion were increased (OR MF 14.5; 95% CI 1.3–159; OR transversus abdominis 6.2; 95% CI = 0.8–48.6).

As size and ability to contract trunk muscles are modifiable factors, further intervention studies targeting motor control of these muscles may be warranted.

Basketball is a high-intensity team sport that requires speed and multidirectional movements, in addition to robustly training energy systems. Thus, this study aims to provide descriptive data on the physical, physiological, and neuromuscular characteristics in elite female basketball players according to athletes' positions on the court.

Eighteen elite female athletes (25.7 ± 4.4 years old) from the elite Brazilian female basketball team participated in this study. On the first day, multiple laboratory and field tests were performed during a training camp, including body composition, vertical jumps, isokinetic strength, and running cardiopulmonary exercise testing (CPET). On the subsequent day, a repeated-sprint ability test was performed on an official basketball court. One-way ANOVA followed by post hoc tests was used for statistical analysis. The significance level was set for the P < 0.05 for all analyses.

There were significant differences in the physical and performance characteristics between positions. Centers, relative to guards and forwards, were significantly (P ≤ 0.03 for all) heavier (17%–25%), taller (6%–12%), had greater fat percentage (22%–28%), lower VO_2max (21%–26%), higher quadriceps peak torque (17%–30%), lower jump height (27%–58%), less peak force (15%–48%), and lower speed (peak and acceleration) in the repeated sprints.

Overall, physical capacities were able to discriminate athletes' court positions in elite female basketball, as many variables regarding body composition, cardiorespiratory fitness, neuromuscular and repeated-sprint performance displayed medium-to-large effects size. In general, Guards showed to be lighter, shorter, and fitter than their counterparts. Moreover, they presented better neuromuscular performance (isokinetic knee strength, jump, and repeated-sprint ability performance).

The aim of this study was to examine the peak locomotor demands of match play and determine if these situations are replicated in training, and analyze their dynamics throughout the competitive microcycle in professional female soccer players based on their positions.

Measurements such as distance covered (DIS), high-speed running distance (HSRD), sprint distance (SPD), accelerating distance (ACC_DIS), decelerating distance (DEC_DIS), and high metabolic load distance (HMLD) were registered during 1, 3, 5 and 10-min peak locomotor in both competitive matches (MD) and training sessions (ranked based on the number of days remaining until the next match, namely MD-4, MD-3, MD-2, and MD-1) within a competitive mesocycle.

Central defenders were found to cover significantly less HMLD than full-backs and forwards, regardless of the time frame, as well as less HMLD than center midfielders in the 3, 5 and 10-min time frames. Only in MD-3 did players exhibit a similar HMLD to MD, regardless of the analyzed time frame. Players covered significantly less HSRD and SPD in MD-2 and MD-1 compared to MD-3, and less HSRD in MD-4 compared to MD-3. Additionally, HSRD and SPD were significantly higher in MD-4 than in MD-1. There were no significant differences in HSRD or SPD relative to match play workload observed between positions within the same training session.

The microcycle showed a non-linear training load, with higher external loads in central sessions (e.g., MD-3) and tapering strategies at the end of the microcycle in peak locomotor demands.

This study aimed to describe athlete workload over the course of a four-year collegiate lacrosse career.

Workload was evaluated each day of training and games using global positioning system microtechnology. Total workload for each athlete was calculated for each season of each year for total distance, high-intensity distance, accelerations, decelerations, and sprints. Data were tabulated as absolute and relative workloads with absolute workload representing an individual athlete and relative workload representing that athlete’s percentage of team mean workload.

The workload of the entire lacrosse team was collected over four years containing the full career of six athletes. Across the five workload variables analyzed, athletes either maintained a workload near team mean workload or demonstrated an increase in workload towards the end of their careers.

As careers progressed, the variation in athlete workload decreased, and athletes approached the team’s average workload. Microtechnology may be useful in monitoring athlete workload over the course of a career.