Effect of Body Position and Support Surface on the Postural Control Challenge During the Pallof Press Exercise: A Smartphone Accelerometer-Based Study

Background and objectives: Although different variations of the Pallof press exercise are commonly performed in sports and fitness settings to increase core stability, the intensity/difficulty of these variations is unknown and therefore it is difficult to control the training load and establish exercise progressions. This study aimed to compare and rank the postural control challenge imposed by five different isometric variations of the Pallof press exercise through a smartphone accelerometer placed on the participants' pelvis and to explore sex differences in the lumbopelvic postural control during the exercise performance. Materials and Methods: Twelve physically active participants completed two testing sessions in which they performed two sets of five different isometric variations of the Pallof press exercise (changing the body position and/or the support surface: kneeling on a foam pad, feet together standing on the floor, tandem stance on the floor, feet together standing on a hemisphere ball, and tandem stance on a hemisphere ball). After confirming the acceleration data reliability (intraclass correlation coefficients ≥ 0.72 and typical errors ≤ 17%), a repeated measure ANOVA was carried out to classify the Pallof press variations according to the postural control challenge imposed on the participants and to analyze sex differences on postural control. Results: Significant effects were found for the within-subject factor exercise variations but not for the between-subject factor sex. Pairwise comparisons showed that the exercise variations performed on the hemisphere ball (feet together standing: 0.55 m/s2; tandem stance: 0.61 m/s2) imposed higher postural control demands than those performed on the other surfaces (kneeling on a foam pad: 0.17 m/s2; feet together standing on the floor: 0.22 m/s2; tandem stance on the floor: 0.31 m/s2). In addition, the tandem stance on the floor produced higher lumbopelvic accelerations than the Pallof press kneeling variation. Conclusions: The Pallof press performance in standing rather than kneeling (i.e., reducing the base of support and raising the center of gravity and the height of the lateral force applied by the elastic band) and on a hemisphere ball increased the exercise difficulty compared to more stable surfaces. This information could help to modulate the difficulty and establish progressions for this exercise in physically active young males and females.

Recruit Fitness Standards From a Large Law Enforcement Agency: Between-Class Comparisons, Percentile Rankings, and Implications for Physical Training

Lockie, RG, Dawes, JJ, Orr, RM, and Dulla, JM. Recruit fitness standards from a large law enforcement agency: Between-class comparisons, percentile rankings, and implications for physical training. J Strength Cond Res 34(4): 934-941, 2020-Law enforcement can be a physically demanding profession. Many agencies use a "one-size-fits-all" academy training approach, which may not be optimal for all recruits. There is also little information that benchmarks fitness of law enforcement recruits. The purpose of this study was to analyze between-academy class differences in fitness, as well as produce normative data for the development of strength and conditioning programs. A retrospective analysis of 908 recruits (761 men and 147 women), comprising 11 classes from one agency, was used. Fitness assessment data included push-ups, sit-ups, and mountain climbers in 120 seconds; pull-ups; 201-m run; and 2.4-km run. A one-way analysis of variance with a Bonferroni post hoc adjustment revealed that fitness varied significantly between classes. Class 11 completed less sit-ups than 6 other classes (p ≤ 0.033) and were slower in the 201-m and 2.4-km run than 5 classes (p ≤ 0.005). Class 7 completed less push-ups than 3 classes (p ≤ 0.036) and less mountain climbers and were slower in the 201-m run than 5 classes (p ≤ 0.005). Individual recruit analysis and percentile data indicated a wide spread of all assessment results and the effects upon female recruits. For example, 81% of women completed ≤2 pull-ups and were in the bottom 2 percentile bands; 72-76% of women were in the bottom 3 bands for push-ups and the 201-m run. Fitness varies from class-to-class, and female recruits will generally be less physically fit. Training staff should ideally implement individualized, ability-based programming where appropriate to train their recruits.

Physical Fitness Characteristics That Relate to Work Sample Test Battery Performance in Law Enforcement Recruits

This study determined relationships between an agency-specific fitness test battery (PT500), and a work sample test battery (WSTB) in law enforcement recruits. Retrospective analysis on 219 males and 34 females from one agency was conducted. The PT500 comprised: push-ups, sit-ups, and mountain climbers in 120 s; pull-ups; and 201 m and 2.4 km runs. The WSTB comprised: 99 yard (90.53 m) obstacle course (99OC); body drag (BD) with a 165 pound (75 kg) dummy; 6 foot (1.83 m) chain link fence (CLF) and solid wall (SW) climb; and 500 yard (457.2 m) run (500R). Partial correlations, controlling for sex, calculated PT500 and WSTB relationships (p < 0.05). Stepwise regression determined whether fitness predicted WSTB performance. The 500R related to all PT500 assessments (r range = −0.127–0.574), 99OC related to all bar push-ups and mountain climbers, and BD related to none. The CLF related to sit-ups, pull-ups, and 2.4 km run; SW related to mountain climbers, pull-ups, and 2.4 km run (r range = −0.127–−0.315). Push-ups, pull-ups, and 2.4 km run were involved in predictive relationships for 99OC, CLF, SW, and 500R (r² range = 0.217–0.500). To perform better in the WSTB and job-specific tasks, developing upper-body strength and aerobic fitness may be beneficial.