Paddling Performance in Recreational and Competitive Junior Surfers

Abstract

Purpose: The primary purpose of this thesis was to investigate surf-paddling performance, the surf popup manoeuvre (i.e., prone to standing position) and maximalleg power in junior male recreational and competitive surfers. Four independent studies were conducted with the aims to: i. Develop reliable testing methods of assessing maximal-paddling performance in surfers (Study 1), ii. Determine the aerobic power and paddling economy in junior male recreational surfers (SurfersREC) and junior male competitive surfers (SurfersCOMP) (Study 2), iii. Measure maximal-paddling performance and the accumulated O2 (AO2) deficit of a 30-s Wingate Anaerobic Test for paddling (WAnTPADDLING) in SurfersREC and SurfersCOMP (Study 3), and iv. Characterise the timing and magnitude of the vertical ground reaction forces produced during a surf popup manoeuvre in SurfersREC and SurfersCOMP; measure maximal-leg power in SurfersREC and SurfersCOMP; and measure the influence of paddling on the popup maneuver and maximal leg power in SurfersREC (Study 4). Methods: All subjects were junior male surfers aged 16-20 yr. SurfersCOMP were members of the Australian Junior National Team and had been competing nationally for a minimum of 2 yr in national age-group events. SurfersREC had been surfing for a minimum of 4 yr and participating in surfing at least 2 session/wk, but had not participated in competitive surfing events, other than their local board-riding events (< 6 event/yr). Participation numbers for each group included; i, Study 1: eleven SurfersCOMP (17 &plusmn; 1 yr, 61.9 &plusmn; 3.1 kg, 173 &plusmn; 2 cm), ii, Study 2: eight SurfersREC (18&plusmn;2 yr; 66.8&plusmn;13 kg, 175&plusmn;10.3 cm) and eight male SurfersCOMP (18&plusmn;1 yr; 68.0 &plusmn;11.7 kg, 172.9&plusmn;9.6 cm), iii, Study 3: eight SurfersREC (18&plusmn;2 yr, 66.7&plusmn;6.3 kg, 169&plusmn;10 cm) and eight SurfersCOMP (18&plusmn;1 yr, 68.9&plusmn;47 kg, 170&plusmn;5 cm), iv, Study 4: ten SurfersREC (17&plusmn;1 yr, 68.2&plusmn;6.2 kg, 179&plusmn;5 cm) and ten SurfersCOMP (17 &plusmn; 1 yr, 62.9&plusmn;9.9 kg, 172&plusmn;8cm) .All paddling tests were performed on a stationary swim-bench ergometer with pulmonary gas exchange measured breath-by-breath using a metabolic measurement system. Aerobic power was determined using an incremental-paddling test to exhaustion and paddling economy measured during paddling at four, 3-min constant-load work stages. Anaerobic power was measured from a 10-s maximal-paddle test and the 30-s WAnTPADDLING test. The AO2 deficit was determined during the WAnTPADDLING as a measure of the contribution of the anaerobic energy systems to the total energy demand of the test. The timing and magnitude of the vertical ground reaction forces produced during the popup were measured on an inground force plate. Maximal vertical jump height was measured on the force plate and used as a measure of leg power. Relationships between paddling, the popup, and leg power were investigated before and after 25 min of paddling on the swim-bench ergometer, designed to replicate a competitive surfing heat. Results: Study 1 established that peak power determined during a 10-s maximalpaddling test on a swim-bench ergometer is a reliable method both trial-to-trial (r = 0.995, p < 0.001) and day-to-day (r = 0.983, p < 0.001) to determine maximal-paddling power in surfers. Study 2 showed that there were no differences between SurfersREC and SurfersCOMP for peak O2 uptake (2.5 &plusmn; 0.5 L/min vs. 2.6 &plusmn; 0.4 L/min, respectively) and economy (21.8 &plusmn; 3.1 % vs. 23.8 &plusmn; 4.0 %, respectively). There were no significant correlations between aerobic power and economy with surfing experience (number of yr surfing) or frequency (session/wk). During submaximal constant-load paddling blood lactate was greater in SurfersREC (2.4 &plusmn; 0.9 mmol/L) compared to SurfersCOMP (1.6 &plusmn; 0.5 mmol/L). In Study 3 peak power (SurfersREC = 292 &plusmn; 56 W vs. SurfersCOMP = 404 &plusmn; 98 W, p = 0.014), mean power (SurfersREC = 236 &plusmn; 59 W vs. SurfersCOMP = 335 &plusmn; 74 W, p = 0.010), and the AO2 deficit (SurfersREC =1.14 &plusmn; 0.38 L vs. SurfersCOMP = 1.60 &plusmn; 0.31 L, p = 0.022) determined during the 30-s WAnTPADDLING were all greater in SurfersCOMP when compared to SurfersREC. No differences were observed between SurfersREC and SurfersCOMP for peak O2 uptake (2.5 &plusmn; 0.2 L/min vs. 2.7 &plusmn; 0.1 &plusmn; L/min, respectively) and paddling economy (19.6 &plusmn; 6.9 % vs. 21.1 &plusmn; 4.9 %). Significant correlations were observed between surfing experience and frequency with the WAnTPADDLING peak power and AO2 deficit. Consistent with study 2, from the incremental paddling test no correlations were observed between surfing experience and frequency and peak O2 uptake and paddling economy. Study 4 revealed no differences between SurfersREC and SurfersCOMP in the timing and magnitude of the vertical ground reaction forces produced during the popup manoeuvre. There were no differences in the leg power as a measure of jump height between SurfersREC (38.2 &plusmn; 4.7 cm) and SurfersCOMP (40.0 &plusmn; 9.2 cm). Following 25 min of intermittent surfboard paddling there was a decrease (t = 4.553, p = 0.001) in maximal vertical jump height in SurfersREC (post paddle = 34.0 &plusmn; 5.1 cm). Conclusions: No differences in aerobic power and paddling economy between SurfersCOMP and SurfersREC and a greater anaerobic power and accumulated O2 deficit in SurfersCOMP compared to SurfersREC suggests that the measures of anaerobic performance are more closely related to surfing ability than measures of aerobic performance. No correlations between aerobic power and paddling economy with surfing experience and participation frequency, but significant correlations between anaerobic power and the accumulated O2 deficit with surfing experience and participation frequency reveal that measures of anaerobic performance are more closely associated with surfing experience and participation frequency than measures of aerobic performance. A decrease in maximal vertical jump height following surfboard paddling suggests that paddling may influence leg power possibly necessary for subsequent wave-riding performance. Collectively these findings suggest that recreational and competitive surfing results in significant changes in the anaerobic energy system, more so that the aerobic energy system and than a bout of paddling can reduce leg power.