myUNB News
News for Faculty and Staff

Faculty of Kinesiology Thesis Oral Examination - Master of Science in Kinesiology - Brandon Richards

Author: Leslie Harquail

Posted on Aug 19, 2019

Category: News and Notices

The Thesis titled, "Motor Unit Recruitment Patterns in Traditional Strength Loading and Peak Average Power Loading Protocols," will be defended by Brandon Richards on Tuesday, Aug. 20, at 1:30 p.m. in the Kinesiology Building,  214. 

All are welcome.

ABSTRACT
Peak average power (PAP) loading demonstrates similar strength responses when compared to
traditional strength (TS) loading methods. The motor unit recruitment strategies of peak average
power loading (PAP) have yet to be explained.

The purpose of this research was to:
1) determine if an isokinetic loading method could be used to simulate PAP isotonic loading, and

2) to assess the motor unit recruitment strategies of the PAP loading method compared to TS
loading. A total of 30 (15 males, 15 females) healthy participants (23.1 ± 3.0 yrs.; 173.3 ± 7.9
cm; 76.6 ± 13.6 kg) were recruited. The study consisted of three testing sessions: a baseline-
testing session and two experimental data collection sessions randomized in order (isokinetic
contraction condition, performed using an isokinetic dynamometer, and an isotonic contraction
condition, back squats). Within each contraction condition, one set of six repetitions occurred for
TS and PAP loading. For the isokinetic contraction condition, TS loading involved participants
using 85% of their maximal torque capacity at 30 deg/s for each repetition, while PAP loading
involved participants using 100% of their maximal torque capacity at 120 deg/s. For the isotonic
contraction condition, TS loading was performed using 85% of their 1-RM, while PAP loading used 67% of their 1-RM. Muscle activity was measured during all sets using high-density electromyography (EMG). The results showed that spatial EMG parameters are not significantly different between the two contraction conditions. The results also demonstrated that TS and PAP loading methods do not differ in their motor unit recruitment patterns. This leads to the following conclusions; 1) isokinetic knee extension are a viable method of assessing TS or PAP loading strategies, and 2) PAP loading has the same motor unit activation pattern as TS loading across a single set of exercise. PAP loading may be a viable method to reduce the strain on the
musculoskeletal system, while still stimulating the high threshold motor units.


 

Category: News and Notices

Article Contact Information

Contact: Leslie Harquail

Email Address: harquail@unb.ca