Close this panel
Browse By Date
Browse By Track
Browse By Poster Author
Browse By Title
Browse By Poster Number
Close this panel

(3) THE RELIABILITY OF POOLED AND INDIVIDUALISED LOAD-VELOCITY PROFILES IN THE POWER CLEAN AND BACK SQUAT


Authors:

Steve W. Thompson, MSc – PhD candidate, Sheffield Hallam University

Harry Banyard – Lecturer in Exercise and Sport Science, Swinburne University

Alan Ruddock – Physiologist and PhD Supervisor, Sheffield Hallam University

David Rogerson – Principal Lecturer and PhD Supervisor, Sheffield Hallam University

Andrew Barnes – Senior Lecturer and Director of Studies, Sheffield Hallam University

Abstract:

PURPOSE: To investigate the reliability of pooled and individualised load-velocity profiles (LVP) in competitive Olympic Weightlifters using the power clean and back squat exercises.

METHODS: Ten competitive weightlifters (mean ± SD; age: 25.0 ± 5.6 y; body mass: 73.6 ± 13.9 kg; stature: 169.6 ± 6.6 cm) completed baseline one repetition maximum assessments in the free-weight power clean (PC) and back squat (BS) (1RM: 103.0 ± 22.8 kg; 154.4 ± 33.8 kg, respectively). Three LVPs consisting of incremental protocols (PC: 40-100% 1RM; BS: 30-100% 1RM) with mean (MV) and peak (PV) velocity, measured via a linear-position transducer were completed; each separated by 48-96 hours. Intraclass correlation coefficient (ICC), coefficient of variation (CV), standard error of the estimate (SEE), linear regression (r), repeated measures one-way ANOVA (p < 0.05) and effect sizes (d) were used to assess the reliability of the load-velocity relationship for pooled and individualised data. High reliability was defined a priori as: ICC >0.7; CV < 10%; d < 0.2.

RESULTS: MV and PV were highly reliable in PC across all sessions (ICC = 0.97-0.98) and relative loads (ICC = > 0.7; CV = < 10%). Strong ICCs for pooled data (0.98-0.99) and relative loads ( > 0.7) were evident for BS, but with large between-participants variation (MV: 8.72% - 27.04%; PV: 9.93% - 30.71%) (Figure 1). Stronger relationships were found for load and MV (BS: r = 0.95; SEE = 0.09 m.s-1; PC: r = 0.87; SEE = 0.08 m.s-1) than PV (BS: r = 0.81; SEE = 0.22 m.s-1; PC: r = 0.81; SEE = 0.16 m.s-1) in the pooled data. Individualised LVPs were stronger in MV (BS: r = 0.98-1.00; SEE = 0.02-0.06 m.s-1; PC: r = 0.87-0.99; SEE = 0.02-0.06 m.s-1) and PV (BS: r = 0.96-1.00; SEE = 0.03-0.11 m.s-1; PC: r = 0.85-1.00; SEE = 0.02-0.10 m.s-1) than the pooled LVPs (Figure 1).Within-participant variation for 95-100% 1RM was > 10% in BS MV. 1RM data was not statistically significantly different between sessions (p > 0.05, d = ≤ 0.08).

CONCLUSIONS: Performing LVPs across a range of submaximal loads met our criteria for high reliability in the PC, but not the BS (CV > 10%). Nevertheless, the criteria were met when utilising individualised LVPs in BS and PC, suggesting that load-velocity characteristics and neuromuscular recruitment differ across individuals, despite sample homogeneity. MV was more reliable than PV in both lifts, signifying greater stability across concentric muscle actions. Large within-participant variation was found at 95-100% 1RM in BS MV, potentially due to greater reliance on the mechanical and elastic properties of muscle at heavier loads.

PRACTICAL APPLICATIONS: LVPs can be used for assessing load-velocity relationships and practitioners can be confident that changes in LVPs are unlikely to be due to test-retest error. Individualised LVPs using MV should be utilised for PC and BS. When profiling BS, submaximal loads of up to 90% are recommended to reduce variability in the data.

 

Rate This Poster

Stuff for notes
Stuff for Message board

Share Poster

Help

Technical Support

(877) 426-6323

support@meetingproceedings.com

Feedback

SUBMIT FEEDBACKfeedback icon

We really appreciate your feedback on the eventScribe website. We use the data to improve the experience and simplify the process for users like you.

Comments


Log In / Sign Up


Already have an Event Scheduler or mobile app login? Login with those details. If not, create a login.


Log In   Sign Up
Access your bookmarked poster and notes by logging in ...   Sign up to take notes on poster, bookmark poster, and submit feedback.
 
 
  Lost your access key?      
   
You need to be logged in to bookmark posters, save notes, or rate posters.