High-intensity cycling training:the effect of work-to-rest intervals on running performance measures

The work-to-rest ratio during cycling-based high-intensity interval training (HIT) could be important in regulating physiological and performance adaptations. We sought to determine the effectiveness of cycling-based HIT with different work-to-rest ratios for long-distance running. Thirty-two long-distance runners (age: 39 ± 8 years; sex: 14 men, 18 women; average weekly running training volume: 25 miles) underwent baseline testing (3-km time-trial, V[Combining Dot Above]O2peak and time to exhaustion, and Wingate test) before a 2-week matched-work cycling HIT of 6 × 10-second sprints with different rest periods (30 seconds [R30], 80 seconds [R80], 120 seconds [R120], or control). Three-kilometer time trial was significantly improved in the R30 group only (3.1 ± 4.0%, p = 0.04), whereas time to exhaustion was significantly increased in the 2 groups with a lower work-to-rest ratio (R30 group 6.4 ± 6.3%, p = 0.003 vs. R80 group 4.4 ± 2.7%, p = 0.03 vs. R120 group 1.9 ± 5.0%, p = 0.2). However, improvements in average power production were significantly greater with a higher work-to-rest ratio (R30 group 0.3 ± 4.1%, p = 0.8 vs. R80 group 4.6 ± 4.2%, p = 0.03 vs. R120 group 5.3 ± 5.9%, p = 0.02), whereas peak power significantly increased only in the R80 group (8.5 ± 8.2%, p = 0.04) but not in the R30 group (4.3 ± 6.1%, p = 0.3) or in the R120 group (7.1 ± 7.9%, p = 0.09). Therefore, cycling-based HIT is an effective way to improve running performance, and the type and magnitude of adaptation is dependent on the work-to-rest ratio

ElECTROMYOGRAPHIC COMPARISON OF THE BACK SQUAT AND OVERHEAD SQUAT

The present study sought to compare the electrical activity of core and lower-body muscles during performance of the back squat and overhead squat. Fourteen male rugby union athletes performed repetitions of both squatting movements with 60, 75 and 90% of their respective 3RM loads. Additional comparisons were made with isolation exercises designed to target the core musculature and a further condition to equate the absolute load lifted. The overhead squat resulted in slight increases in activity of the rectus abdominus and external oblique, with larger decreases in activity of the erector spinae and lower-body muscles. The results show that the differences in muscle activity are largely a function of the absolute load lifted and that anterior core muscles are recruited to a greater extent during isolation exercises compared with squatting movements

Concurrent training

Many sports require a range of physical qualities including strength, power and aerobic capacity for optimal performance. Subsequently, training is likely to contain periods where concurrent development of fitness components is required and will typically be classified into two training categories, endurance and strength training. In order to optimize training, the interaction of these fitness components should be considered as endurance training may interfere with resistance training sessions via conflicting molecular signaling which may blunt optimal muscular development. At present, there is a range of conflicting recommendations in the literature due to the challenges of comparing different training studies and the variables which impact upon the magnitude of adaptation; including volume, intensity, sequencing, rest and concurrent training goals. Most importantly, the overall training stress should be considered to limit cumulative fatigue and minimize the potential negative effect on strength adaptations via dampened hypertrophic responses. Inter-session rest should be maximized wherever possible to reduce the interaction between competing molecular signaling pathways. Where required, strength training should be completed after aerobic endurance training to ensure overnight recovery facilitates strength based adaptations. Overall, optimal planning during concurrent training is a complex interaction between a range of variables where strength and conditioning professionals should be conscious of a range of factors and select a training regime that minimized the interference effect but also fits with their own training logistics

Interpreting magnitude of change in strength and conditioning: effect size selection, threshold values and Bayesian updating.

The magnitude of change following strength and conditioning (S&C) training can be evaluated comparing effect sizes to threshold values. This study conducted a series of meta-analyses and compiled results to identify thresholds specific to S&C, and create prior distributions for Bayesian updating. Pre- and post-training data from S&C interventions were translated into standardised mean difference (SMDpre) and percentage improvement (%Improve) effect sizes. Four-level Bayesian hierarchical meta-analysis models were conducted to compare effect sizes, develop prior distributions, and estimate 0.25-, 0.5-, and 0.75-quantiles to determine small, medium, and large thresholds respectively. Data from 643 studies comprising 6574 effect sizes were included in the analyses. Large differences in distributions for both SMDpre and %Improve were identified across outcome domains (strength, power, jump and sprint performance), with analyses of the tails of the distributions indicating potential large overestimations of SMDpre values. Future evaluations of S&C training will be improved using Bayesian approaches featuring the information and priors developed in this study. To facilitate an uptake of Bayesian methods within S&C, an easily accessible tool employing intuitive Bayesian updating was created. It is recommended that the tool and specific thresholds be used instead of isolated effect size calculations and Cohen's generic values when evaluating S&C training

Managing Performance Throughout Periods of Travel

Understanding the impact of travel on physical performance is an increasing area of interest for the strength and conditioning practitioner. Previous research surrounding the effect of travel on the physiology of an athlete has focused on sleep. Of concern to coaches and athletes are strategies to help attenuate any detrimental impact of travel on subsequent performance. The aim of this article is to provide informative practical guidelines for before, during, and after travel that can be implemented by coaches and athletes. The key coping strategies addressed include timed light exposure; managing sleep deprivation and nutritional recommendations

The effects of complex training on neuromuscular development of the lower limbs in youth netball players

Objective: The high prevalence of injury in netball can be associated with intrinsic or extrinsic factors. Female athletes have an increased risk of injury as they enter into maturity due to increased joint laxity and a reduction in neuromuscular control, resulting in altered landing biomechanics and greater knee joint injury risk. This study sought to investigate whether complex training (CT) could improve neuromuscular strength and landing kinematics, thereby reducing injury risk to the knee. Methods: A within subject, repeated measures design was utilised. Ten youth netball academy players (age, 15.3 ± 0.9, years; height, 169.0 ± 7.0, cm; body mass, 62.2 ± 6.9, kg) participated and attended one familiarisation and two testing sessions (pre- and post-intervention). Participants’ were assessed on: countermovement jump (CMJ), landing error score system (LESS), and single leg countermovement jump (SLCMJ) of both limbs. All participants engaged in a 6 week, one day per week, strength training and plyometric intervention for the lower limbs utilising CT. Results: Significant improvements were evidenced for CMJ height (p = 0.001, d = 1.2 “moderate” effect), CMJ peak power output (PPO) (p = 0.001, d = 0.7 “small” effect), LESS (p = 0.002, d = 1.7 “large” effect), and SLCMJ left height (p = 0.01, d = 1.2 “moderate” effect) following the intervention. Conclusion: Performing one CT session a week over 6 weeks enhanced kinematics and performance of jumping activities both bilaterally and unilaterally, it also brought about reductions in asymmetries in young female athletes

Autoregulation in resistance training : addressing the inconsistencies

Autoregulation is a process that is used to manipulate training based primarily on the measurement of an individual's performance or their perceived capability to perform. Despite being established as a training framework since the 1940s, there has been limited systematic research investigating its broad utility. Instead, researchers have focused on disparate practices that can be considered specific examples of the broader autoregulation training framework. A primary limitation of previous research includes inconsistent use of key terminology (e.g., adaptation, readiness, fatigue, and response) and associated ambiguity of how to implement different autoregulation strategies. Crucially, this ambiguity in terminology and failure to provide a holistic overview of autoregulation limits the synthesis of existing research findings and their dissemination to practitioners working in both performance and health contexts. Therefore, the purpose of the current review was threefold: first, we provide a broad overview of various autoregulation strategies and their development in both research and practice whilst highlighting the inconsistencies in definitions and terminology that currently exist. Second, we present an overarching conceptual framework that can be used to generate operational definitions and contextualise autoregulation within broader training theory. Finally, we show how previous definitions of autoregulation fit within the proposed framework and provide specific examples of how common practices may be viewed, highlighting their individual subtleties

Electromyographic and Kinetic Comparison of the Back Squat and Overhead Squat

The purpose of this study was to compare muscle activity and kinetics during the back squat and overhead squat performed at 3 relative intensities (60, 75, and 90% 3 repetition maximum). Fourteen subjects (age, 26 ± 7 years; height, 182.5 ± 13.5 cm; body mass, 90.5 ± 17.5 kg) performed each exercise using a within-subjects crossover design. In addition, a selection of trunk isolation exercises were included to provide additional comparisons. Squats were performed on a force platform with electromyographic activity of the anterior deltoid, rectus abdominis (RA), external oblique (EO), erector spinae (ES), gluteus maximus, vastus lateralis, biceps femoris, and lateral gastrocnemius recorded throughout. The overhead squat demonstrated significantly greater (p ≤ 0.05) activity in the anterior trunk muscles (RA and EO) during the eccentric phase. However, the magnitudes of the differences were relatively small (approximately 2–7%). In contrast, the back squat displayed significantly greater (p ≤ 0.05) activity in the posterior aspect of the trunk ES and all lower-body muscles during the concentric phase. Kinetic comparisons revealed that significantly greater peak force (p ≤ 0.05) was developed during the back squat. Electromyographic comparisons between the trunk isolation exercises and squat variations demonstrated substantially greater anterior trunk activity during the isolation exercises, whereas the highest activity in the posterior aspect of the trunk was obtained during the squats (p ≤ 0.05). The results of the study do not support the hypothesis that the overhead squat provides a substantially greater stimulus for developing the trunk musculature compared with the back squat

Kinetic and electromyographic comparison of the back squat and overhead squat

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