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Mr John McMahon's Outputs (100)

Variability of plyometric and ballistic exercise technique maintains jump performance (2018)
Journal Article
Chandler, P., Greig, M., & McMahon, J. (2018). Variability of plyometric and ballistic exercise technique maintains jump performance. Journal of Strength and Conditioning Research, 32(6), 1571-1582. https://doi.org/10.1519/JSC.0000000000002572

The aim of this study was to investigate changes in vertical jump technique over the course of a training session. Twelve plyometric and ballistic exercise trained male athletes (age = 23.4 ± 4.6 years, body mass = 78.7 ± 18.8 kg, height = 177.1 ± 9.... Read More about Variability of plyometric and ballistic exercise technique maintains jump performance.

Comparison of the force-, velocity- and power-time curves between the concentric-only and eccentric-concentric bench press exercises (2018)
Journal Article
Pérez-Castilla, A., Comfort, P., McMahon, J., Pestaña-Melero, F., & García-Ramos, A. (2020). Comparison of the force-, velocity- and power-time curves between the concentric-only and eccentric-concentric bench press exercises. Journal of Strength and Conditioning Research, 34(6), 1618-1624. https://doi.org/10.1519/JSC.0000000000002448

The aim of this study was to compare the temporal and mechanical variables between the concentric-only and eccentric-concentric bench press (BP) variants. Twenty-one men (age: 22.0±4.2 years, body mass: 73.4±7.7 kg, height: 177.2±8.0 cm; one-repetiti... Read More about Comparison of the force-, velocity- and power-time curves between the concentric-only and eccentric-concentric bench press exercises.

Lack of effect of ankle position during the Nordic curl on muscle activity of the biceps femoris and medial gastrocnemius (2017)
Journal Article
Comfort, P., Regan, A., Herrington, L., Thomas, C., McMahon, J., & Jones, P. (2017). Lack of effect of ankle position during the Nordic curl on muscle activity of the biceps femoris and medial gastrocnemius. Journal of Sport Rehabilitation, 26(3), 202-207. https://doi.org/10.1123/jsr.2015-0130

Context:
Regular performance (~2×/wk) of Nordic curls has been shown to increase hamstring strength and reduce the risk of hamstring strain injury, although no consensus on ankle position has been provided.

Objective:
To compare the effects of p... Read More about Lack of effect of ankle position during the Nordic curl on muscle activity of the biceps femoris and medial gastrocnemius.

The effects of a four week jump-training program on frontal plane projection angle in female gymnasts (2017)
Journal Article
Colclough, A., Munro, A., Herrington, L., McMahon, J., & Comfort, P. (2018). The effects of a four week jump-training program on frontal plane projection angle in female gymnasts. Physical Therapy in Sport, 30, 29-33. https://doi.org/10.1016/j.ptsp.2017.11.003

Objectives: To investigate the effects of a four week jump training program on frontal plane projection angle (FPPA) in young female gymnasts.
Design: Intervention study, consisting of a four week jump training program performed for 15 minutes as... Read More about The effects of a four week jump-training program on frontal plane projection angle in female gymnasts.

Returners exhibit greater jumping performance improvements during a peaking phase compared to new players on a volleyball team (2017)
Journal Article
Bazyler, C., Mizuguchi, S., Kavanaugh, A., McMahon, J., Comfort, P., & Stone, M. (2017). Returners exhibit greater jumping performance improvements during a peaking phase compared to new players on a volleyball team. International Journal of Sports Physiology and Performance, 13(6), 709-716. https://doi.org/10.1123/ijspp.2017-0474

Purpose: To determine if jumping performance changes during a peaking phase differed between returners and new players in a female collegiate volleyball team and to determine which variables best explained the variation in performance changes. Metho... Read More about Returners exhibit greater jumping performance improvements during a peaking phase compared to new players on a volleyball team.

The effect of hip joint angle on isometric midthigh pull kinetics (2017)
Journal Article
Dos'Santos, T., Thomas, C., Jones, P., McMahon, J., & Comfort, P. (2017). The effect of hip joint angle on isometric midthigh pull kinetics. Journal of Strength and Conditioning Research, 31(10), 2748-2757. https://doi.org/10.1519/JSC.0000000000002098

The aim of this study were to compare isometric midthigh pull (IMTP) peak force (PF), time-specific force values (100-, 150-, and 200 ms), rate of force development (RFD) at predetermined time bands (0–100, 0–150, and 0–200 ms) and net forces between... Read More about The effect of hip joint angle on isometric midthigh pull kinetics.

Influence of dynamic strength index on countermovement jump force-, power-, velocity-, and displacement-time curves (2017)
Journal Article
McMahon, J., Jones, P., Dos'Santos, T., & Comfort, P. (2017). Influence of dynamic strength index on countermovement jump force-, power-, velocity-, and displacement-time curves. Sports, 5(4), 72-83. https://doi.org/10.3390/sports5040072

The dynamic strength index (DSI), often calculated as the ratio of countermovement jump (CMJ) propulsion peak force to isometric mid-thigh pull (IMTP) peak force, is said to inform whether ballistic or maximal strength training is warranted for a giv... Read More about Influence of dynamic strength index on countermovement jump force-, power-, velocity-, and displacement-time curves.

Relationships between isometric force-time characteristics and dynamic performance (2017)
Journal Article
Dos'Santos, T., Thomas, C., Comfort, P., McMahon, J., & Jones, P. (2017). Relationships between isometric force-time characteristics and dynamic performance. Sports, 5(3), https://doi.org/10.3390/sports5030068

The purpose of this study was to explore the relationships between isometric mid-thigh pull (IMTP) force-time characteristics (peak force and time-specific force vales (100–250 ms)) and dynamic performance and compare dynamic performance between stro... Read More about Relationships between isometric force-time characteristics and dynamic performance.

Comment on : "Anthropometric and physical qualities of elite male youth rugby league players" (2017)
Journal Article
McMahon, J., Jones, P., & Comfort, P. (2017). Comment on : "Anthropometric and physical qualities of elite male youth rugby league players". Sports Medicine, 47(12), 2667-2668. https://doi.org/10.1007/s40279-017-0771-6

We read with interest the recent review on anthropometric and physical qualities of elite male youth rugby league players by Till et al. and congratulate the authors for producing a very informative review. However, we would like to raise an issue th... Read More about Comment on : "Anthropometric and physical qualities of elite male youth rugby league players".

Assessment of loaded squat jump height with a free-weight barbell and Smith machine : comparison of the take-off velocity and flight time procedures (2017)
Journal Article
Pérez-Castilla, A., McMahon, J., Comfort, P., & García-Ramos, A. (2020). Assessment of loaded squat jump height with a free-weight barbell and Smith machine : comparison of the take-off velocity and flight time procedures. Journal of Strength and Conditioning Research, 34(3), 671-677. https://doi.org/10.1519/JSC.0000000000002166

The aims of this study were to compare the reliability and magnitude of jump height between the two standard procedures of analysing force platform data to estimate jump height (take-off velocity [TOV] and flight time [FT]) in the loaded squat jump (... Read More about Assessment of loaded squat jump height with a free-weight barbell and Smith machine : comparison of the take-off velocity and flight time procedures.

Comparison of methods of calculating dynamic strength index (2017)
Journal Article
Comfort, P., Thomas, C., Dos'Santos, T., Jones, P., Suchomel, T., & McMahon, J. (2017). Comparison of methods of calculating dynamic strength index. International Journal of Sports Physiology and Performance, 13(3), 320-325. https://doi.org/10.1123/ijspp.2017-0255

Purpose: To determine the reliability and variability of dynamic strength index (DSI) calculated from squat jump (SJ) (DSI-SJ) versus countermovement jump (CMJ) (DSI-CMJ) peak force (PF) and to compare DSI values between methods. Methods: Male youth... Read More about Comparison of methods of calculating dynamic strength index.

Countermovement jump phase characteristics of senior and academy rugby league players (2017)
Journal Article
McMahon, J., Murphy, S., Rej, S., & Comfort, P. (2017). Countermovement jump phase characteristics of senior and academy rugby league players. International Journal of Sports Physiology and Performance, 12(6), 803-811. https://doi.org/10.1123/ijspp.2016-0467

Purpose:

Gross measures of countermovement jump (CMJ) performance are commonly used to track maturational changes in neuromuscular function within rugby league (RL). The purpose of this study was to conduct both a gross and a more detailed tempor... Read More about Countermovement jump phase characteristics of senior and academy rugby league players.

Influence of reactive strength index modified on force- and power-time curves (2017)
Journal Article
McMahon, J., Jones, P., Suchomel, T., Lake, J., & Comfort, P. (2017). Influence of reactive strength index modified on force- and power-time curves. International Journal of Sports Physiology and Performance, 13(2), 220-227. https://doi.org/10.1123/ijspp.2017-0056

Purpose: The reactive strength index modified (RSImod) has been recently identified and validated as a method of monitoring countermovement jump (CMJ) performance. The kinetic and kinematic mechanisms that optimize a higher RSImod score are, however,... Read More about Influence of reactive strength index modified on force- and power-time curves.

Sex differences in countermovement jump phase characteristics (2017)
Journal Article
McMahon, J., Rej, S., & Comfort, P. (2017). Sex differences in countermovement jump phase characteristics. Sports, 5(1), 8. https://doi.org/10.3390/sports5010008

The countermovement jump (CMJ) is commonly used to explore sex differences in neuromuscular function, but previous studies have only reported gross CMJ measures or have partly examined CMJ phase characteristics. The purpose of this study was to explo... Read More about Sex differences in countermovement jump phase characteristics.

Changes in strength, power, and speed across a season in English county cricketers (2017)
Journal Article
Carr, C., McMahon, J., & Comfort, P. (2017). Changes in strength, power, and speed across a season in English county cricketers. International Journal of Sports Physiology and Performance, 12(1), 50-55. https://doi.org/10.1123/ijspp.2015-0524

PURPOSE: Previous research has investigated changes in athletes' strength, power, and speed performances across the competitive season of many sports, although this has not been explored in cricketers. The aim of this study was to investigate changes... Read More about Changes in strength, power, and speed across a season in English county cricketers.

Within- and between-session reliability of medial gastrocnemius architectural properties (2016)
Journal Article
McMahon, J., Turner, A., & Comfort, P. (2016). Within- and between-session reliability of medial gastrocnemius architectural properties. Biology of Sport, 33(2), 185-188. https://doi.org/10.5604/20831862.1200511

This study aimed to determine the within- and between-session reliability of medial gastrocnemius (MG)
architecture (e.g. muscle thickness (MT), fascicle length (FL) and pennation angle (PA)), as derived via
ultrasonography followed by manual digit... Read More about Within- and between-session reliability of medial gastrocnemius architectural properties.