Effects of 5-Week Foam Rolling Intervention on Range of Motion and Muscle Stiffness
Kiyono, R, Onuma, R, Yasaka, K, Sato, S, Yahata, K, and Nakamura, M. Effects of 5-week foam rolling intervention on range of motion and muscle stiffness. J Strength Cond Res 36(7): 1890–1895, 2022—In clinical and sports settings, foam rolling (FR) intervention is widely used to increase the range of motion (ROM). However, the chronic effects of FR on ROM and muscle stiffness are unclear. The aim of this study was to investigate the effects of 5-week FR intervention on dorsiflexion ROM (DFROM) and shear elastic modulus of the medial gastrocnemius (MG) muscle. Accordingly, 30 healthy young adults were enrolled and random...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

The BDNF-Increasing Allele is Associated With Increased Proportion of Fast-Twitch Muscle Fibers, Handgrip Strength, and Power Athlete Status
In conclusion, the rs10501089 A-allele is associated with increased proportion of fast-twitch muscle fibers and greater handgrip strength, and these may explain, in part, the association between the AA/AG genotypes and power athlete status. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Improved Ankle Mobility After a 4-Week Training Program Affects Landing Mechanics: A Randomized Controlled Trial
This study examined the effects of a 4-week ankle mobility intervention on landing mechanics. Twenty subjects with restricted ankle dorsiflexion range of motion (DF ROM) were allocated to either a strength training only (n = 9) or a strength training and ankle mobility program (n = 11). Subjects performed a weight-bearing lunge test and bilateral drop-landings before and after the intervention. Normalized peak vertical ground reaction force (vGRF), time to peak vGRF, and loading rate were calculated, alongside sagittal-plane initial contact angles, peak angles, and sagittal-plane joint displacement for the ankle, knee, and...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Complex Vs. Compound Training on Competitive Throwing Performance
Thomas, K, Spyridon, M, Nikolaos, Z, Angeliki-Nikolleta, S, Giorgos, K, Giorgos, G, and Gerasimos, T. Effects of complex vs. compound training on competitive throwing performance. J Strength Cond Res 36(7): 1866–1874, 2022—The purpose of this study was to investigate the effects of complex (CPX; strength and power exercises in pairs) vs. compound (CPD; strength and power exercises in different days) training on competitive track and field throwing performance. Ten well-trained throwers (7 male throwers and 3 female throwers) followed a 34-week periodized training program including 2 preparation periods. During the wint...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Can Foot Anthropometry Predict Vertical Jump Performance?
Hawley, VS, Gurchiek, RD, and van Werkhoven, H. Can foot anthropometry predict vertical jump performance? J Strength Cond Res 36(7): 1860–1865, 2022—Vertical jumping is an important element of many sporting activities, and whether anthropometric adaptations can predict jumping performance is of interest. Few studies have specifically considered anthropometric measures of the foot and its link to performance. Furthermore, previous studies have mainly focused on a male subject pool, and whether relationships are consistent across sexes is unclear. The purpose of this study was to investigate relationships between common ...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Stronger Subjects Select a Movement Pattern That May Reduce Anterior Cruciate Ligament Loading During Cutting
Davies, WT, Ryu, JH, Graham-Smith, P, Goodwin, JE, and Cleather, DJ. Stronger subjects select a movement pattern that may reduce anterior cruciate ligament loading during cutting. J Strength Cond Res 36(7): 1853–1859, 2022—Increased strength has been suggested to reduce the incidence of anterior cruciate ligament (ACL) injury as part of wider neuromuscular training programs; however, the mechanism of this is not clear. Cutting is a high-risk maneuver for ACL injury, but limited research exists as to how strength affects sagittal plane biomechanics during this movement. Sixteen subjects were split into a stronger and we...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Muscular Activation Patterns During Exercise on the Treadmill, Stepper, and Elliptical Trainer
Eken, MM, Withers, A, Flanagan, K, Burger, J, Bosch, A, and Lamberts, RP. Muscular activation patterns during exercise on the treadmill, stepper, and elliptical trainer. J Strength Cond Res 36(7): 1847–1852, 2022—Because of the low-impact, the stepper and elliptical trainer are popular alternatives to running when runners sustain running-related injuries. Muscular effort is expected to be lower during exercise on the stepper and elliptical trainer compared with running. The aim of this study was to quantify this by comparing muscular effort when exercising at similar moderate-to-high exercise intensities on a treadmill...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Muscle Activity, Leg Stiffness, and Kinematics During Unresisted and Resisted Sprinting Conditions
This study aimed to compare muscle activity, leg stiffness, and kinematics (contact and flight time [FT], stride length and frequency, and trunk angle [TA]) of unloaded sprinting to resisted sprint (RST) using different loads. Twelve male rugby players (age: 23.5 ± 5.1 years; height: 1.79 ± 0.04 m; body mass 82.5 ± 13.1 kg) performed 30-m sprints using different loading conditions (0, 10, 30 and 50% of velocity loss—Vloss—from the maximum velocity reached under unloaded condition). Muscle activity from 4 muscles (biceps femoris long head, rectus femoris [RF], gluteus medius and gastrocnemius), leg stiffness (Kleg), ...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of 2.4 kg of Proximal External Loading on 5-km Running Performance
This study examined effects of modest loading via a ∼2.4-kg soft and malleable weighted compression garment on overground running performance. Former and current collegiate cross-country runners (5 women and 6 men) completed 2 outdoor, solo road course runs 7 days apart on a familiar training route. During the first run (CON) subjects ran as closely as possible to their goal pace for a “hard speed day” workout based on predetermined paces according to current training level. During a subsequent run, subjects attempted to match their pace with aid from global positioning system watches and splits verbally announced on...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Do Faster, Stronger, and More Powerful Athletes Perform Better in Resisted Sprints?
In conclusion, differences in speed, strength, and power abilities may explain, at least partially, the individual response of each athlete during sprinting towing a sled, especially with heavier sled loads. Thus, faster, stronger, and more powerful athletes require heavier sled loads (relative to %BM) to experience similar exercise intensities. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Utility of a Shortened Isometric Midthigh Pull Protocol for Assessing Rapid Force Production in Athletes
Suarez, DG, Carroll, KM, Slaton, JA, Rochau, KG, Davis, MW, and Stone, MH. Utility of a shortened isometric midthigh pull protocol for assessing rapid force production in athletes. J Strength Cond Res 36(7): 1819–1825, 2022—The purpose of this investigation was to determine the magnitude of difference, reliability, and relationship to performance of a shortened isometric midthigh pull (IMTP) protocol. Fourteen strength-trained men (age: 26.8 ± 5.0 years, height: 176.3 ± 6.9 cm, body mass: 86.8 ± 13.9 kg, and training age: 8.5 ± 6.9 years) performed 1-second (SHORT) and traditional (TRAD) IMTP protocols during conse...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Comparison of Traditional and Rest-Redistribution Sets on Indirect Markers of Muscle Damage Following Eccentric Exercise
Merrigan, JJ, Jones, MT, Malecek, J, Padecky, J, Omcirk, D, Xu, N, Peñailillo, L, and Tufano, JJ. Comparison of traditional and rest-redistribution sets on indirect markers of muscle damage following eccentric exercise. J Strength Cond Res 36(7): 1810–1818, 2022—The purpose was to investigate the effect of rest-redistribution (RR) on muscle damage after eccentric knee extensions. After 2 weeks of eccentric familiarization, 11 resistance-trained men performed 2 work-matched isokinetic unilateral eccentric knee extension protocols at 60°·s−1 using a crossover design, separated by 7 days. Subjects performed 40 repeti...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Influence of Second Generation Oral Contraceptive Use on Adaptations to Resistance Training in Young Untrained Women
Dalgaard, LB, Jørgensen, EB, Oxfeldt, M, Dalgaard, EB, Johansen, FT, Karlsson, M, Ringgaard, S, and Hansen, M. Influence of second generation oral contraceptive use on adaptations to resistance training in young untrained women. J Strength Cond Res 36(7): 1801–1809, 2022—The study purpose was to determine effects of using second generation oral contraceptives (OC) on muscle adaptations to resistance training in young untrained women. Twenty users and 18 nonusers of OC completed a 10-week supervised progressive resistance training program. Before and after the intervention, muscle cross-sectional area (mCSA) of the qua...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Does the Activity in Scapular Muscles During Plyometric Exercises Change When the Kinetic Chain Is Challenged?—An EMG Study
Werin, MB, Maenhout, AG, Icket, J, Jacxsens, N, Kempkes, E, and Cools, AM. Does the activity in scapular muscles during plyometric exercises change when the kinetic chain is challenged?—An EMG study. J Strength Cond Res 36(7): 1793–1800, 2022—Plyometric exercises for the shoulder are used in rehabilitation and in workout regime when the sport demands high speed power training. The aim of this clinical laboratory electromyography (EMG) study was to determine whether scapular muscle performance differs during plyometric shoulder exercises when changing the demand on the kinetic chain. Thirty healthy overhead athletes, ...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research

Differences in Electromygraphic Activity of the Middle and the Lower Serratus Anterior Fibers During Open and Closed Kinematics Exercises
Ratanapinunchai, J and Madeeyoh, I. Differences in electromygraphic activity of the middle and the lower serratus anterior fibers during open and closed kinematics exercises. J Strength Cond Res 36(7): 1788–1792, 2022—This paper seeks to determine differences in muscle activation between the middle (MSA) and the lower serratus anterior (LSA) fibers during 3 exercises. Fifteen healthy men were recruited for the study. Bench push-up plus (BPUP), unstable BPUP (UPUP), and resisted shoulder flexion (RSF) with 10 repetitions at maximum weight were tested. The normalized electromyographic (EMG) activity of the MSA and the LS...
Source: Journal of Strength and Conditioning Research - June 27, 2022 Category: Sports Medicine Tags: Original Research Source Type: research