Purpose: To compare the effects of increased load of low- versus high-intensity endurance training on performance and physiological adaptations in well-trained endurance athletes. Methods: Following an 8-week preintervention period, 51 (36 men and 15 women) junior cross-country skiers and biathletes were randomly allocated into a low-intensity (LIG, n = 26) or high-intensity training group (HIG, n = 25) for an 8-week intervention period, load balanced using the overall training impulse score. Both groups performed an uphill running time trial and were assessed for laboratory performance and physiological profiling in treadmill running and roller-ski skating preintervention and postintervention. Results: Preintervention to postintervention changes in running time trial did not differ between groups (P = .44), with significant improvements in HIG (−2.3% [3.2%], P = .01) but not in LIG (−1.5% [2.9%], P = .20). There were no differences between groups in peak speed changes when incremental running and roller-ski skating to exhaustion (P = .30 and P = .20, respectively), with both modes being significantly improved in HIG (2.2% [3.1%] and 2.5% [3.4%], both P < .01) and in roller-ski skating for LIG (1.5% [2.4%], P < .01). There was a between-group difference in running maximal oxygen uptake changes (P = .04), tending to improve in HIG (3.0% [6.4%], P = .09) but not in LIG (−0.7% [4.6%], P = .25). Changes in roller-ski skating peak oxygen uptake differed between groups (P = .02), with significant improvements in HIG (3.6% [5.4%], P = .01) but not in LIG (−0.1% [0.17%], P = .62). Conclusion: There was no significant difference in performance adaptations between increased load of low- versus high-intensity training in well-trained endurance athletes, although both methods improved performance. However, increased load of high-intensity training elicited better maximal oxygen uptake adaptations compared to increased load of low-intensity training.
Rune K. Talsnes, Roland van den Tillaar, and Øyvind Sandbakk
Markus Tilp, Lukas Kitzberger, Gudrun Schappacher-Tilp, Philipp Birnbaumer, and Peter Hofmann
Purpose: Reported relationships between electromyographic (EMG) thresholds and systemic thresholds based on lactate, ventilation, or heart rate are contradictory. This might be related to the complexity of the investigated whole-body movements involving many muscles with different activation patterns. Therefore, the aim of the study was to investigate these relationships during an incremental single-joint exercise. Methods: Eighteen male subjects (29.7 [4.4] y) performed single-arm elbow flexions on a biceps curl machine with loads increasing every minute until exhaustion. EMG signals of the main elbow flexors (short and long head of the biceps brachii, flexor carpi radialis, and brachioradialis) as well as gas exchange variables, blood lactate concentration, and heart rate were measured, and 2 turn points based on a 3-phase model of metabolism were determined for each variable. Results: The first and second turn points for EMG were determined at 32.0% to 33.1% and 64.4% to 66.5% of maximal achieved performance (maximum weight), respectively. Systemic turn points were determined at 33.3% to 34.4% and 65.9% to 66.7% of maximum weight and were not significantly different from EMG turn points. Furthermore, systemic and EMG turn points showed a strong or very strong relationship at the first (ρ = .54–.93, P < .05) and second turn point (ρ = .76–.93, P < .01). Conclusions: A close relationship between EMG and systemic turn points could be confirmed for the applied movement of a small muscle group. The determination of local single muscle thresholds using EMG provides additional muscle-specific information about performance-limiting properties of muscles involved in endurance-type incremental exercise.
Siobhán O’Connor, Wesley O’Brien, and Peter Lacey
Community sports play an important role in maintaining sporting participation across all ages, from childhood to adulthood. Maintaining participation for females, however, can be a challenge. Injuries can negatively impact sporting participation, both in the short and long term. Thus, reducing the risk of injuries in community sports is essential. While there are developed injury prevention programs available, the uptake of such programs in community sports can be limited. Here, we outline how a female community sport in Ireland, namely, the Camogie Association, has developed and implemented an evidence-based strategy to improve the uptake of an injury prevention program nationally across all ages of their membership. We use the RE-AIM (Reach, Effectiveness, Adoption, Implementation and Maintenance) sports setting matrix as a guiding tool for evaluating this strategy. Varying settings and levels were targeted in this six-step implementation sequence, including the national sporting organisation, regional sporting organisations, alongside the individual coaches and players. The main outcomes of the strategy were that the Camogie Association formally adopted the developed injury prevention program (the Camogie Injury Prevention Program) and the adapted age appropriate programs from 8 years of age and upward. The Camogie Association also embedded this program within their coaching training course. The developed education workshop successfully improved coaches’ attitudes and perceived ability to implement the Camogie Injury Prevention Program. The majority (72.5%) of coaches, 4 weeks after conducting the workshop, had implemented the program, and 95% felt the program could be maintained over multiple seasons. This program may provide guidance to similar national or regional sporting bodies that want to embed injury prevention programs within their respective governing body and maximise the implementation of an injury prevention program by their coaches and players.
Alice Iannaccone, Andrea Fusco, Antanas Skarbalius, Audinga Kniubaite, Cristina Cortis, and Daniele Conte
Purpose: Assessing the relationship between external load (EL) and internal load (IL) in youth male beach handball players. Methods: A total of 11 field players from the Lithuanian U17 beach handball team were monitored across 14 training sessions and 7 matches. The following EL variables were assessed by means of inertial movement units: PlayerLoad™, accelerations, decelerations, changes of direction, and jumps and total of inertial movements. IL was assessed objectively and subjectively using the summated heart rate zones and training load calculated via session rating of perceived exertion, respectively. Spearman correlations (ρ) were used to assess the relationship between EL and IL. The interindividual variability was investigated using linear mixed models with random intercepts with IL as dependent variable, PlayerLoad™ as the independent variable, and players as random effect. Results: The lowest significant (P < .05) relationship was for high jumps with objective (ρ = .56) and subjective (ρ = .49) IL. The strongest relationship was for PlayerLoad™ with objective (ρ = .9) and subjective (ρ = .84) IL. From the linear mixed model, the estimated SD of the random intercepts was 19.78 arbitrary units (95% confidence interval, 11.75–33.31); SE = 5.26, and R2 = .47 for the objective IL and 6.03 arbitrary units (95% confidence interval, 0.00–7330.6); SE = 21.87; and R2 = .71 for the subjective IL. Conclusions: Objective and subjective IL measures can be used as a monitoring tool when EL monitoring is not possible. Coaches can predict IL based on a given EL by using the equations proposed in this study.
Matej Vajda and Eva Piatrikova
Purpose: To assess the relationship between flat-water tests and canoe slalom performance on 4 different grades of water terrain difficulty. Methods: Nineteen elite canoe slalom athletes racing in category K1 men (n = 7), K1 women (n = 5), or C1 men (n = 7) completed flat-water tests: (1) a sprint with a turn to the preferred side, (2) a sprint with a turn to the nonpreferred side, (3) a sprint with a turn to both sides, and (4) a 12 × 15-m all-out shuttle test. Canoe slalom performance was measured in competitions with 4 different grades of water terrain difficulty. Results: There were relationships between 12 × 15-m all-out shuttle test and performance across different water terrain grades (P < .001; r = .706–.871)); however, the magnitude of the relationship decreased with increasing water terrain grade difficulty. Similar trends were observed for the sprint with a turn to the preferred side (r = .588–.884), sprint with a turn to the nonpreferred side (r = .544–.864), and sprint with a turn to both sides (r = .638–.909). In addition, small to moderate differences were observed between preferred and nonpreferred side in K1 women (P = .050, ES = 0.37), K1 men (P = .019, ES = 0.66), and C1 men (P = .003, ES = 0.69). Conclusion: The novel battery of flatwater tests can be used to measure the performance-related physical fitness of canoe slalom athletes. Sprint with a turn to the preferred side and sprint with a turn to the nonpreferred side can also be used to assess the imbalance between an athlete’s preferred and nonpreferred side. Accordingly, to our findings, practitioners could consider adapting the training program in preparation for important competitions specifically to water terrain difficulty grades where these competitions will be organized.
Teun van Erp, Taco van der Hoorn, Marco J.M. Hoozemans, Carl Foster, and Jos J. de Koning
Purpose: To determine if workload and seasonal periods (preseason vs in season) are associated with the incidence of injuries and illnesses in female professional cyclists. Methods: Session rating of perceived exertion was used to quantify internal workload and was collected from 15 professional female cyclists, from 33 athlete seasons. One week (acute) workload, 4 weeks (chronic) workload, and 3 acute:chronic workload models were analyzed. Two workload models are based on moving averages of the ratios, the acute:chronic workload ratio (ACWR), and the ACWR uncoupled (ACWRuncoup). The difference between both is the chronic load; in ACWR, the acute load is part of the chronic load, and in ACWRuncoup, the acute and chronic load are uncoupled. The third workload model is based on exponentially weighted moving averages of the ratios. In addition, the athlete season is divided into the preseason and in season. Results: Generalized estimating equations analysis was used to assess the associations between the workload ratios and the occurrence of injuries and illnesses. High values of acute workload (P = .048), ACWR (P = .02), ACWRuncoup (P = .02), exponentially weighted moving averages of the ratios (P = .01), and the in season (P = .0001) are significantly associated with the occurrence of injury. No significant associations were found between the workload models, the seasonal periods, and the occurrence of illnesses. Conclusions: These findings suggest the importance of monitoring workload and workload ratios in female professional cyclists to lower the risk of injuries and therefore improve their performances. Furthermore, these results indicate that, in the preseason, additional stressors occur, which could lead to an increased risk of injuries.
Cassandra Iannucci and Melissa Parker
The past decade has seen an increased focus on student voice in physical education; yet, the majority reflects the thoughts, feelings, and experiences of agency of secondary-level students. It has been suggested that the perspectives and experiences of students in primary physical education remain largely absent from the literature. Therefore, the purpose of this review was to answer the question “what peer-reviewed data on student voice in primary physical education was published between January 1990 and March 2020?” This article provides a map of 89 articles that accessed student voice in primary physical education. Conclusions highlight a need for democratic possibilities for primary students to engage and contribute to their physical education learning experiences as well as a continued exploration of the implementation and impact of authentic methods of accessing and responding to student voice in primary physical education.