This study investigated the repeated bout effect of 3 typical lower body resistance-training sessions on maximal and submaximal effort running performance. Twelve resistance-untrained men (age, 24 ± 4 years; height, 1.81 ± 0.10 m; body mass, 79.3 ± 10.9 kg; peak oxygen uptake, 48.2 ± 6.5 mL·kg·min; 6-repetition maximum squat, 71.7 ± 12.2 kg) undertook 3 bouts of resistance-training sessions at 6-repetitions maximum. Countermovement jump (CMJ), lower-body range of motion (ROM), muscle soreness, and creatine kinase (CK) were examined prior to and immediately, 24 h (T24), and 48 h (T48) after each resistance-training bout. Submaximal (i.e., below anaerobic threshold (AT)) and maximal (i.e., above AT) running performances were also conducted at T24 and T48. Most indirect muscle damage markers (i.e., CMJ, ROM, and muscle soreness) and submaximal running performance were significantly improved (P < 0.05; 1.9%) following the third resistance-training bout compared with the second bout. Whilst maximal running performance was also improved following the third bout (P < 0.05; 9.8%) compared with other bouts, the measures were still reduced by 12%-20% versus baseline. However, the increase in CK was attenuated following the second bout (P < 0.05) with no further protection following the third bout (P > 0.05). In conclusion, the initial bout induced the greatest change in CK; however, at least 2 bouts were required to produce protective effects on other indirect muscle damage markers and submaximal running performance measures. This suggests that submaximal running sessions should be avoided for at least 48 h after resistance training until the third bout, although a greater recovery period may be required for maximal running sessions.

Heilbronn, BE, Doma, K, Gormann, D, Schumann, M, and Sinclair, WH. Effects of periodized vs. nonperiodized resistance training on army-specific fitness and skills performance. J Strength Cond Res 34(3): 738–753, 2020—This study investigated the effects of periodized resistance training (PRD) and nonperiodized resistance training (NPRD) on army-specific fitness and skills performance measures. Forty-nine serving members of the Australian Army were randomly assigned to 1 of 3 training groups: PRD, NPRD, or no-resistance training (NRT). Resistance training (RT) was performed during PRD and NPRD twice a week for 9 weeks, over a 15-week period, as part of a structured strength and conditioning program. Baseline, mid- and post-testing measures included anthropometric, strength, and army-specific outcome measures. Results indicated that participants who undertook RT significantly improved in 3 repetition maximum (3RM) squat, deadlift, and floor press for both RT groups, at mid- and post-testing (p < 0.05), when compared with NRT. Significant improvements were also observed in 5-km weight load marching postintervention similarly for PRD (p < 0.05) and NPRD (p < 0.01) and simulated fire and movement for both RT groups at both time points (p < 0.01), compared with the NRT group (p > 0.05). Although little difference was observed between periodization models, the current findings suggest greater advantage in developing army-specific performances if a structured RT protocol is included in a generic physical training program compared with a NRT protocol. Therefore, a structured RT program should be considered for military personnel aiming to optimize army-specific fitness and skills performance.

Introduction Physical training is important to prepare soldiers for the intense occupational demands in the military. However, current physical training may not address all fitness domains crucial for optimizing physical readiness and reducing musculoskeletal injury. The effects of nontraditional military physical training on fitness domains have been inconsistently reported, which limits the design of the ideal training program for performance optimization and injury prevention in the military. The aim of this systematic review was to identify the effects of exercise training on various fitness domains (i.e., aerobic fitness, flexibility, muscular endurance, muscular power, muscular strength, and occupationally specific physical performance) that contribute to occupational performance and musculoskeletal injury risk in military personnel. Methods An extensive literature search was conducted in January 2021 and was subsequently updated in July 2021 and December 2021. Included studies consisted of comparative groups of healthy military personnel performing traditional and nontraditional military physical training with at least one assessment representative of a fitness domain. Study appraisal was conducted using the PEDro scale. Meta-analysis was conducted via forest plots, standard mean difference (SMD, effect size), and intertrial heterogeneity (I2). Results From a total of 7,350 records, 15 studies were identified as eligible for inclusion in this review, with a total of 1,613 participants. The average study quality via the PEDro score was good (5.3/10; range 4/10 to 6/10). Nontraditional military physical training resulted in greater posttraining values for muscular endurance (SMD = 0.46; P = .004; I2 = 68%), power (SMD = 1.57; P &lt; .0001; I2 = 90%), strength via repetition maximum testing (SMD = 1.95; P &lt; .00001; I2 = 91%), and occupationally specific physical performance (SMD = 0.54; P = .007; I2 = 66%) compared to the traditional group. There was no significant difference for aerobic fitness (SMD = −0.31; P = .23; I2 = 86%), flexibility (SMD = 0.58; P = .16; I2 = 76%), and muscular strength via maximal voluntary contraction (SMD = 0.18; P = .28; I2 = 66%) between training groups. Conclusions The current systematic review identified that nontraditional military physical training had a greater posttraining effect on muscular endurance, power, strength measured via repetition maximum, and occupationally specific physical performance compared to traditional military physical training. Overall, these findings suggest that nontraditional military physical training may be beneficial in optimizing occupational performance while potentially reducing musculoskeletal injury risk.

Introduction Prevention of musculoskeletal injury is vital to the readiness, performance, and health of military personnel with the use of specialized systems (e.g., force plates) to assess risk and/or physical performance of interest. This study aimed to identify the reliability of one specialized system during standard assessments in military personnel. Methods Sixty-two male and ten female Australian Army soldiers performed a two-leg countermovement jump (CMJ), one-leg CMJ, one-leg balance, and one-arm plank assessments using a Sparta Science force plate system across three testing sessions. Sparta Science (e.g., total Sparta, balance and plank scores, jump height, and injury risk) and biomechanical (e.g., average eccentric rate of contraction, average concentric force, and sway velocity) variables were recorded for all sessions. Mean ± SD, intraclass correlation coefficients (ICCs), coefficient of variation, and bias and limits of agreement were calculated for all variables. Results Mean results were similar between sessions 2 and 3 (P &gt; .05). The relative reliability for the Sparta Science (ICC = 0.28-0.91) and biomechanical variables (ICC = 0.03-0.85) was poor to excellent. The mean absolute reliability (coefficient of variation) for Sparta Science variables was similar to or lower than that of the biomechanical variables during the CMJ (1-10% vs. 3-7%), one-leg balance (4-6% vs. 9-14%), and one-arm plank (5-7% vs. 12-17%) assessments. The mean bias for most variables was small (&lt;5% of the mean), while the limits of agreement varied with most unacceptable (±6-87% of the mean). Conclusions The reliability of most Sparta Science and biomechanical variables during standard assessments was moderate to good. The typical variability in metrics documented will assist practitioners with the use of emerging technology to monitor and assess injury risk and/or training interventions in military personnel.

Introduction Military personnel are required to undertake rigorous physical training to meet the unique demands of combat, often leading to high levels of physiological stress. Inappropriate recovery periods with these high levels of physical stress may result in sub-optimal training and increased risk of injury in military personnel. However, no reviews have attempted to examine the magnitude of training-induced stress following military training activities. The aim of this systematic review was to assess the magnitude of physiological stress (physical, hormonal, and immunological) following task-specific training activities in military personnel. Methods An extensive literature search was conducted within CINAHL, PubMed, Scopus, SportDiscus, and Web of Science databases with 7,220 records extracted and a total of 14 studies eligible for inclusion and evaluation. Study appraisal was conducted using the Kmet scale. Meta-analysis was conducted via forest plots, with standard mean difference (SMD, effect size) and inter-trial heterogeneity (I2) calculated between before (preactivity) and after (12–96 hours postactivity) military-specific activities for biomarkers of physiological stress (muscle damage, inflammation, and hormonal) and physical performance (muscular strength and power). Results Military training activities resulted in significant levels of muscle damage (SMD = −1.28; P = .003) and significant impairments in strength and power (SMD = 0.91; P = .008) and testosterone levels (SMD = 1.48; P = .05) up to 96 hours postactivity. There were no significant differences in inflammation (SMD = −0.70; P = .11), cortisol (SMD = −0.18; P = .81), or insulin-like growth factor 1 (SMD = 0.65; P = .07) when compared to preactivity measures. Conclusions These findings indicate that assessments of muscle damage, anabolic hormones like testosterone, strength, and power are effective for determining the level of acute stress following military-specific activities. With regular monitoring of these measures, appropriate recovery periods may be implemented to optimize training adaptations and occupational performance, with minimal adverse training responses in military personnel.