Tags

Type your tag names separated by a space and hit enter

Load-Power Relationship During a Countermovement Jump: A Joint Level Analysis.
J Strength Cond Res. 2018 Apr; 32(4):955-961.JS

Abstract

Williams, KJ, Chapman, DW, Phillips, EJ, and Ball, N. Load-power relationship during a countermovement jump: A joint level analysis. J Strength Cond Res 32(4): 955-961, 2018-This study aimed to investigate whether hip, knee, and ankle peak power is influenced by the relative load lifted, altering the joint and system load-power relationship during a countermovement jump (CMJ). Twenty-three male national representative athletes (age: 20.3 ± 3.1 years, squat 1 repetition maximum [1RM]: 133.8 ± 24.8 kg) completed 3 CMJs at relative barbell loads of 0, 10, 20, 30, and 40% of an athlete's estimated back squat 1RM. Ground reaction force and joint kinematics were captured using a 16 camera motion capture array integrated with 2 in-ground triaxial force plates. Hip ((Equation is included in full-text article.)= 20%, range 0 > 40%), knee ((Equation is included in full-text article.)= 0%, 0 > 20%), and ankle ((Equation is included in full-text article.)= 40%, 0 > 40%) peak power was maximized at different percentages of absolute strength, with an athlete-dependent variation in load-power profiles observed across all lower-body joints. A decrease in system (body + barbell mass) peak power was significantly (p ≤ 0.05, r = 0.45) correlated with a reduction in knee peak power. Timing of instantaneous system and hip peak power occurred significantly closer to toe-off as load increased. The findings highlight that the generation and translation of lower-body joint power is influenced by external load and athlete-dependent traits. This subsequently alters the load-power profile at a system level, explaining the broad spectrums of loads reported to optimize system power during a CMJ. When training, we recommend that a combination of barbell loads based on assorted percentages of the estimated 1RM be prescribed to optimize joint and system power during a CMJ.

Links

Publisher Full Text (DOI)

Authors+Show Affiliations

Williams KJ
Strength and Conditioning, Australian Institute of Sport, Bruce, Australia. Research Institute for Sport and Exercise, University of Canberra, Bruce, Australia. College of Education, Psychology and Social Work, Flinders University, Bedford Park, Australia.
Chapman DW
Research Institute for Sport and Exercise, University of Canberra, Bruce, Australia. Physiology, Australian Institute of Sport, Bruce, Australia.
Phillips EJ
Movement Science, Australian Institute of Sport, Bruce, Australia.
Ball NB
Research Institute for Sport and Exercise, University of Canberra, Bruce, Australia.

MeSH

AdolescentAnkle JointAthletesBiomechanical PhenomenaHip JointHumansKnee JointLower ExtremityMaleMuscle StrengthMuscle, SkeletalResistance TrainingYoung Adult

Pub Type(s)

Journal Article

Language

eng

PubMed ID

29334580

Citation

Williams, Kym J., et al. "Load-Power Relationship During a Countermovement Jump: a Joint Level Analysis." Journal of Strength and Conditioning Research, vol. 32, no. 4, 2018, pp. 955-961.
Williams KJ, Chapman DW, Phillips EJ, et al. Load-Power Relationship During a Countermovement Jump: A Joint Level Analysis. J Strength Cond Res. 2018;32(4):955-961.
Williams, K. J., Chapman, D. W., Phillips, E. J., & Ball, N. B. (2018). Load-Power Relationship During a Countermovement Jump: A Joint Level Analysis. Journal of Strength and Conditioning Research, 32(4), 955-961. https://doi.org/10.1519/JSC.0000000000002432
Williams KJ, et al. Load-Power Relationship During a Countermovement Jump: a Joint Level Analysis. J Strength Cond Res. 2018;32(4):955-961. PubMed PMID: 29334580.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Load-Power Relationship During a Countermovement Jump: A Joint Level Analysis. AU - Williams,Kym J, AU - Chapman,Dale W, AU - Phillips,Elissa J, AU - Ball,Nick B, PY - 2018/1/16/pubmed PY - 2018/8/28/medline PY - 2018/1/16/entrez SP - 955 EP - 961 JF - Journal of strength and conditioning research JO - J Strength Cond Res VL - 32 IS - 4 N2 - Williams, KJ, Chapman, DW, Phillips, EJ, and Ball, N. Load-power relationship during a countermovement jump: A joint level analysis. J Strength Cond Res 32(4): 955-961, 2018-This study aimed to investigate whether hip, knee, and ankle peak power is influenced by the relative load lifted, altering the joint and system load-power relationship during a countermovement jump (CMJ). Twenty-three male national representative athletes (age: 20.3 ± 3.1 years, squat 1 repetition maximum [1RM]: 133.8 ± 24.8 kg) completed 3 CMJs at relative barbell loads of 0, 10, 20, 30, and 40% of an athlete's estimated back squat 1RM. Ground reaction force and joint kinematics were captured using a 16 camera motion capture array integrated with 2 in-ground triaxial force plates. Hip ((Equation is included in full-text article.)= 20%, range 0 > 40%), knee ((Equation is included in full-text article.)= 0%, 0 > 20%), and ankle ((Equation is included in full-text article.)= 40%, 0 > 40%) peak power was maximized at different percentages of absolute strength, with an athlete-dependent variation in load-power profiles observed across all lower-body joints. A decrease in system (body + barbell mass) peak power was significantly (p ≤ 0.05, r = 0.45) correlated with a reduction in knee peak power. Timing of instantaneous system and hip peak power occurred significantly closer to toe-off as load increased. The findings highlight that the generation and translation of lower-body joint power is influenced by external load and athlete-dependent traits. This subsequently alters the load-power profile at a system level, explaining the broad spectrums of loads reported to optimize system power during a CMJ. When training, we recommend that a combination of barbell loads based on assorted percentages of the estimated 1RM be prescribed to optimize joint and system power during a CMJ. SN - 1533-4287 UR - https://www.unboundmedicine.com/medline/citation/29334580/Load_Power_Relationship_During_a_Countermovement_Jump:_A_Joint_Level_Analysis_ DB - PRIME DP - Unbound Medicine ER -