Date of Award
Thesis - ECU Access Only
Doctor of Philosophy
School of Medical and Health Sciences / Centre for Exercise and Sports Science Research
Professor Ken Nosaka
200-m sprint kayaking requires repeated cyclic force production, and athletes typically incorporate resistance training programs aimed at improving muscular strength and power and the ability to produce high forces over the course of the race (i.e. 31-40 s). Whilst upper body strength and whole-body maximal oxygen uptake have been associated with faster race times in sub-elite athletes, it is not known whether strength and aerobic capacity, or changes in them, influence performances in high-level kayak athletes.
In Study 1 of the present thesis, relationships between isoinertial strength (i.e., bench press, bench row, chin-up and deadlift), VO2max, and 200-m race times were quantified in 22 national- and elite-level kayak athletes, including three Olympic finalists. Strong relationships were found between race time and both upper body strength (r = -0.81 to -0.73) and VO2max (r = -0.70), but not deadlift strength. However, isometric force testing might be of greater diagnostic value as it allows for the quantification of time-specific force production (i.e. matching the time available for force production within the stroke) at joint angles similar to those of the limbs during the kayak stroke.
Therefore, Study 2 examined relationships between lower-body isometric force and 200- m race times. Relationships between the mid-thigh pull force and 200-m race time were found to be poor-to-moderate (r = -0.49 to 0.07), suggesting (along with the results of Study 1) that maximal lower body force production might not be as closely associated with 200-m kayak time as upper body strength.
Whether performances in isometric bench press and bench row tests might be more associated with 200-m race time than isoinertial tests was then examined in Study 3. Despite limited test familiarisation, isometric force produced to time points >0.2 s after force onset were both reliable (ICCs > 0.91 to 0.97 for bench press measured to different time points) and strongly-to-very strongly related (r > -0.51 to -0.80) to both race times and performances in the corresponding isoinertial strength tests. However, relationships with race time for the isometric tests were of a similar magnitude to those of the isoinertial tests, and they thus provided no additional information than those tests.
In Study 4, pacing patterns and stroke kinetics were quantified during 200-m kayak races in 19 high- and elite-level athletes. The athletes executed “fast-start” pacing plans in which the acceleration rate to maximal velocity was a key determinant in race times (r=-0.95 ± 0.04). Further, better-performed athletes used higher stroke rates, although stroke rate did not discriminate between those better athletes. Within the cohort of faster athletes, stroke length (r=-0.48 to -0.85) and the effective work produced within each stroke (r = -0.81 to -0.95) were determining factors in final race times. Athletes who displayed lower fatigue-induced decrements in stroke length and effective work per stroke had faster race times.
In the final study, the effects of altering muscular strength on 200-m race time as well as changes in aerobic capacity and kayak technique were examined through the use of an 8-week eccentric-biased strength training (ECC-b) block as compared to their standard concentric-eccentric (CON-ECC) strength training. ECC-b led to greater improvements than CON-ECC in race time (adjusted mean difference: 1.86 s), stroke length (0.19 to 0.43 m), and effective work per stroke (14.7 to 19.1), total isoinertial strength (the sum of all lifts =15.3 kg), isometric strength (232 to 293 N) and absolute (0.18 Lmin-1) and relative VO2max (3.74 mL kg∙min-1). CON-ECC resulted in a reduced performance in the race time (? s) and some tests, perhaps due to training-induced fatigue.
When viewed collectively, the studies of the current thesis indicate that upper body muscular contractile force capacity and wholebody maximal oxygen uptake are key factors influencing 200-m kayak race time. These factors, as well as 200-m time and stroke effectiveness, were positively influenced by the completion of a block of heavy, eccentric-biased strength training even though the contraction mode and movement pattern of exercises was dissimilar to that of the kayak stroke. Future research might examine the effects of eccentric-biased strength training on performance in other sports such as cycling, swimming and rowing, which require the repeated performance of concentric muscular contractions
Pickett, C. (2020). Factors determining 200-m kayak performance: Muscle strength, aerobic capacity, stroke kinematics and training. https://ro.ecu.edu.au/theses/2325
Available for download on Friday, July 01, 2022