A Research Note Investigating the Leg Tuck and Plank With Potential Impacts for Occupational Testing.

ABSTRACT: Gonzalez, SM, Withrow, KL, Rubin, DA, Lynn, SK, Dawes, JJ, Orr, RM, and Lockie, RG. A research note investigating the leg tuck and plank with potential impacts for occupational testing. J Strength Cond Res 37(10): 2076-2079, 2023-The U.S. Army recently replaced the leg tuck with the plank in their physical ability testing. There has been limited analysis of whether these 2 tests correlate, have any relationships with body composition and strength, or are sex-neutral. Forty-nine civilian college students (28 males, 21 females) were recruited as surrogates for tactical personnel. The following were measured: height, body mass, body fat percentage (BF%), and muscle mass percentage (MM%) measured through bioelectrical impedance analysis, grip strength, leg tuck, and plank. Independent t -tests were calculated to determine between-sex differences for all variables ( p < 0.05). Partial correlations controlling for sex were used to compute relationships between the leg tuck, plank, and other variables. Stepwise regression controlling for sex derived predictive relationships for the leg tuck and plank. Males were taller, had greater body mass, MM%, and were superior in grip strength and the leg tuck; females had greater BF%. There were no significant between-sex differences for the plank. The leg tuck correlated with BF%, MM%, grip strength, and the plank ( r = ±0.333-0.524). In addition to the leg tuck, the plank correlated with BF% ( r = -0.288). The leg tuck was predicted by sex, grip strength, and the plank (adjusted r2 = 0.662). No variables predicted the plank. As there were no between-sex differences and sex was not a plank predictor, it appears this test minimized sex differences on task performance in civilians. However, the leg tuck and plank likely measure different qualities; further research is needed on job task relationships.

Army Combat Fitness Test Relationships to Tactical Foot March Performance in Reserve Officers' Training Corps Cadets.

The Army Combat Fitness Test (ACFT), consisting of deadlift, standing power throw, hand release push-up, sprint-drag-carry, leg tuck or plank, and 2-mile run, is the United States Army's new fitness test. The ACFT is designed to measure multiple fitness components required to perform combat tasks. One critical task is the tactical foot march (TFM), where soldiers cover long distances while carrying loads comprised of mission-essential equipment. As the ACFT is meant to predict soldier task performance, determining the relationships between the ACFT and the TFM is important. Data from 29 cadets (♂ = 20, ♀ = 9) from one university Reserve Officers' Training Corps program were analyzed. The ACFT was recorded in raw and scaled scores. The TFM was performed over 6.44 km, with time recorded. Cadets carried a 15.88-kg rucksack, fighting load carrier, 3-L hydration pack, and replica M4 carbine. Independent samples t-tests evaluated ACFT and TFM between-sex differences. Partial correlations, controlling for sex, determined ACFT event and TFM relationships. Male cadets outperformed females in all ACFT tasks (p ≤ 0.039), except the push-up. ACFT total score, leg tuck, 2-mile run, and sprint-drag-carry showed large correlations with the TFM (r = ±0.463-0.531, p ≤ 0.026). Aerobic and anaerobic capacity and upper body/trunk strength were important fitness components for cadet TFM performance.