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This study explored the effects of 4 bench-press (BP) training programs with different velocity-loss (VL) thresholds (0%, 15%, 25%, and 50%) on strength gains and neuromuscular adaptations. Methods: Forty-six resistance-trained men (22.8 [4.4] y) were randomly assigned into 4 groups that differed in the VL allowed within the set: 0% (VL0), 15% (VL15), 25% (VL25), and 50% (VL50). Training loads (40%–55% 1-repetition maximum), frequency (2 sessions/wk), number of sets (3), and interset recovery (4 min) were identical for all groups. Participants completed the following tests before and after an 8-week (16-session) BP training program: (1) maximal isometric test, (2) progressive loading test, and (3) fatigue test in the BP exercise. During all tests, triceps brachii muscle electromyography was assessed. Results: After completing the resistance-training program, no significant group × time interactions were noticed for isometric and dynamic BP strength variables. The dose–response relationship exhibited an inverted U-shaped relationship pattern, with VL25 showing the greatest effect sizes for almost all strength variables analyzed. The total number of repetitions performed during the training program increased as the VL magnitude increased. Conclusions: The group that trained with high VL threshold (50%), which performed a total of 876 repetitions, did not experience additional strength gains compared with those experienced by the 0%, 15%, and 25% of VL groups, which performed significantly fewer repetitions (48, 357, and 547, respectively). These findings suggest that when light loads (40%–55% 1-repetition maximum) are used, low and moderate VL thresholds (0%–25%) provide a higher training efficiency.

Up to 86% of pregnant women will have lumbopelvic pain during the 3rd trimester of pregnancy and women with lumbopelvic pain experience lower health-related quality of life during pregnancy than women without lumbopelvic pain. Several risk factors for pregnancy-related lumbopelvic pain have been identified and include history of low back pain, previous trauma to the back or pelvis and previous pregnancy-related pelvic girdle pain. During pregnancy, women go through several hormonal and biomechanical changes as well as neuromuscular adaptations which could explain the development of lumbopelvic pain, but this remains unclear. The aim of this article is to review the potential pregnancy-related changes and adaptations (hormonal, biomechanical and neuromuscular) that may play a role in the development of lumbopelvic pain during pregnancy. This narrative review presents different mechanisms that may explain the development of lumbopelvic pain in pregnant women. A hypotheses-driven model on how these various physiological changes potentially interact in the development of lumbopelvic pain in pregnant women is also presented. Pregnancy-related hormonal changes, characterized by an increase in relaxin, estrogen and progesterone levels, are potentially linked to ligament hyperlaxity and joint instability, thus contributing to lumbopelvic pain. In addition, biomechanical changes induced by the growing fetus, can modify posture, load sharing and mechanical stress in the lumbar and pelvic structures. Finally, neuromuscular adaptations during pregnancy include an increase in the activation of lumbopelvic muscles and a decrease in endurance of the pelvic floor muscles. Whether or not a causal link between these changes and lumbopelvic pain exists remains to be determined. This model provides a better understanding of the mechanisms behind the development of lumbopelvic pain during pregnancy to guide future research. It should allow clinicians and researchers to consider the mult

Up to 86% of pregnant women will have lumbopelvic pain during the 3rd trimester of pregnancy and women with lumbopelvic pain experience lower health-related quality of life during pregnancy than women without lumbopelvic pain. Several risk factors for pregnancy-related lumbopelvic pain have been identified and include history of low back pain, previous trauma to the back or pelvis and previous pregnancy-related pelvic girdle pain. During pregnancy, women go through several hormonal and biomechanical changes as well as neuromuscular adaptations which could explain the development of lumbopelvic pain, but this remains unclear. The aim of this article is to review the potential pregnancy-related changes and adaptations (hormonal, biomechanical and neuromuscular) that may play a role in the development of lumbopelvic pain during pregnancy. This narrative review presents different mechanisms that may explain the development of lumbopelvic pain in pregnant women. A hypotheses-driven model on how these various physiological changes potentially interact in the development of lumbopelvic pain in pregnant women is also presented. Pregnancy-related hormonal changes, characterized by an increase in relaxin, estrogen and progesterone levels, are potentially linked to ligament hyperlaxity and joint instability, thus contributing to lumbopelvic pain. In addition, biomechanical changes induced by the growing fetus, can modify posture, load sharing and mechanical stress in the lumbar and pelvic structures. Finally, neuromuscular adaptations during pregnancy include an increase in the activation of lumbopelvic muscles and a decrease in endurance of the pelvic floor muscles. Whether or not a causal link between these changes and lumbopelvic pain exists remains to be determined. This model provides a better understanding of the mechanisms behind the development of lumbopelvic pain during pregnancy to guide future research. It should allow clinicians and researchers to consider the mult

BackgroundThe importance of concurrent exercise order for improving endurance and resistance adaptations remains unclear, particularly when sessions are performed a few hours apart. We investigated the effects of concurrent training (in alternate orders, separated by ~3 hours) on endurance and resistance training adaptations, compared to resistance-only training.Materials and methodsTwenty-nine healthy, moderately-active men (mean ± SD; age 24.5 ± 4.7 y; body mass 74.9 ± 10.8 kg; height 179.7 ± 6.5 cm) performed either resistance-only training (RT, n = 9), or same-day concurrent training whereby high-intensity interval training was performed either 3 hours before (HIIT+RT, n = 10) or after resistance training (RT+HIIT, n = 10), for 3 d.wk-1 over 9 weeks. Training-induced changes in leg press 1-repetition maximal (1-RM) strength, countermovement jump (CMJ) performance, body composition, peak oxygen uptake (), aerobic power (), and lactate threshold () were assessed before, and after both 5 and 9 weeks of training.ResultsAfter 9 weeks, all training groups increased leg press 1-RM (~24–28%) and total lean mass (~3-4%), with no clear differences between groups. Both concurrent groups elicited similar small-to-moderate improvements in all markers of aerobic fitness ( ~8–9%; ~16-20%; ~14-15%). RT improved CMJ displacement (mean ± SD, 5.3 ± 6.3%), velocity (2.2 ± 2.7%), force (absolute: 10.1 ± 10.1%), and power (absolute: 9.8 ± 7.6%; relative: 6.0 ± 6.6%). HIIT+RT elicited comparable improvements in CMJ velocity only (2.2 ± 2.7%). Compared to RT, RT+HIIT attenuated CMJ displacement (mean difference ± 90%CI, -5.1 ± 4.3%), force (absolute: -8.2 ± 7.1%) and power (absolute: -6.0 ± 4.7%). Only RT+HIIT reduced absolute fat mass (mean ± SD, -11.0 ± 11.7%).ConclusionsIn moderately-active males, concurrent training, regardless of the exercise order, pr

Van Hooren, B, Bosch, F, and Meijer, K. Can resistance training enhance the rapid force development in unloaded dynamic isoinertial multi-joint movements? A systematic review. J Strength Cond Res 31(8): 2324-2337, 2017-The objectives of this systematic review were to (a) evaluate whether resistance training can improve the rapid force development in unloaded dynamic isoinertial multi-joint movements and (b) investigate whether these effects differ between untrained/ recreationally trained and well-trained individuals. Four electronic databases were screened for studies that measured the effects of resistance training on rapid force development in unloaded dynamic isoinertial multi-joint movements. Twelve studies with a total of 271 participants were included. 10/26 (38%) and 6/14 (43%) of the measures of rapid force development in unloaded dynamic isoinertial multi-joint movements significantly improved following training in the untrained/recreationally trained and well-trained individuals, respectively. Additionally, 7/14 (50%) and 3/12 (25%) of the measures significantly improved during a countermovement and squat jump in the untrained/recreationally trained individuals and 4/6 (67%) and 2/8 (25%) significantly improved during a countermovement and squat jump in the well-trained individuals, respectively. These findings indicate that resistance training has a limited transfer to rapid force development in unloaded dynamic isoinertial multi-joint movements, especially for well-trained individuals and in movements without a countermovement. Furthermore, rapid force development has likely a limited transfer from movements with countermovement to movements without a countermovement and from bilateral movements to unilateral movements. Therefore, it is important to specifically mimic the actual sport movement in order to maximize the transfer of training and testing.

Van Hooren, B, Bosch, F, and Meijer, K. Can resistance training enhance the rapid force development in unloaded dynamic isoinertial multi-joint movements? A systematic review. J Strength Cond Res 31(8): 2324-2337, 2017-The objectives of this systematic review were to (a) evaluate whether resistance training can improve the rapid force development in unloaded dynamic isoinertial multi-joint movements and (b) investigate whether these effects differ between untrained/ recreationally trained and well-trained individuals. Four electronic databases were screened for studies that measured the effects of resistance training on rapid force development in unloaded dynamic isoinertial multi-joint movements. Twelve studies with a total of 271 participants were included. 10/26 (38%) and 6/14 (43%) of the measures of rapid force development in unloaded dynamic isoinertial multi-joint movements significantly improved following training in the untrained/recreationally trained and well-trained individuals, respectively. Additionally, 7/14 (50%) and 3/12 (25%) of the measures significantly improved during a countermovement and squat jump in the untrained/recreationally trained individuals and 4/6 (67%) and 2/8 (25%) significantly improved during a countermovement and squat jump in the well-trained individuals, respectively. These findings indicate that resistance training has a limited transfer to rapid force development in unloaded dynamic isoinertial multi-joint movements, especially for well-trained individuals and in movements without a countermovement. Furthermore, rapid force development has likely a limited transfer from movements with countermovement to movements without a countermovement and from bilateral movements to unilateral movements. Therefore, it is important to specifically mimic the actual sport movement in order to maximize the transfer of training and testing.

Eccentric actions are thought to be particularly important to increase muscle strength and size but are often performed at submaximal intensities during traditional resistance training. The aim of the present study was to compare neuromuscular adaptations from eccentric-overload resistance training (EO) to traditional resistance training (TRT).

Eccentric actions are thought to be particularly important to increase muscle strength and size but are often performed at submaximal intensities during traditional resistance training. The aim of the present study was to compare neuromuscular adaptations from eccentric-overload resistance training (EO) to traditional resistance training (TRT).

Experiment 1: To determine if the magnitude of improvements in athletic performance and the mechanisms driving these adaptations differ in relatively weak individuals exposed to either ballistic power training or heavy strength training. Experiment 2: To determine if the magnitude of performance improvements and the mechanisms driving adaptation to ballistic power training differ between strong and weak individuals. Experiment 3: To determine if ballistic power training and heavy strength training result in specific changes to power absorption (i.e. power generated during the eccentric phase) and production (i.e. power generated during the concentric phase) and if so, whether these changes are influenced by the individual‟s strength level. An additional purpose was to assess whether potential training induced changes in power absorption and production are influenced by alterations to factors commonly associated with SSC function (i.e. rate and magnitude of stretch, time of movement).

Walker, S., Hakkinen, K., Tufano, J., Trezise, J., Haff, G.G., Blazevich, A.J., Newton, R. (2014). Neuromuscular adapatations to traditional versus eccentric-overload resistance training. European Journal of Sports Studies: Supplement to Volume 2. (p. 34.) Available here

Mothersole G., Cronin J.B., & Harris N.K. (2014). Jump-landing program for females: Development of a systematic progression model. Strength and Conditioning Journal, 36(4), 52-64. Available here