Development and validation of a core endurance intervention program: implications for performance in college-age rowers.
Tse MA, McManus AM, Masters RS.
Institute of Human Performance, University of Hong Kong, Pokfulam, Hong Kong. email@example.com
The objective of this study was to examine the effectiveness of a core endurance exercise protocol. Forty-five college-age rowers (age 21 +/- 1.0) were assigned to either a core training group [core group] (n = 25), which took part in a core endurance intervention exercise protocol, or to a control training group [control group] (n = 20), which was not given any specialized core training. Training took place 2 days per week for 8 weeks. Trunk endurance was assessed using flexion, extension, and side flexion tests, whereas a variety of functional performance measures were assessed (vertical jump, broad jump, shuttle run, 40-m sprint, overhead medicine ball throw, 2,000-m maximal rowing ergometer test). The results revealed significant improvement in the two side flexion tests for the core group (p < 0.05). Interestingly, significant differences were noted in the trunk extension test endurance times for the control group (p < 0.05), but not for the core group. No significant differences were found for any of the functional performance tests. In summary, the 8-week core endurance training program improved selected core endurance parameters in healthy young men, but the effectiveness of the core intervention on various functional performance aspects was not supported.
Dietary carbohydrate, muscle glycogen, and power output during rowing training.
Simonsen JC, Sherman WM, Lamb DR, Dernbach AR, Doyle JA, Strauss R.
Exercise Physiology Laboratory, School of Health, Physical Education, and Recreation, Ohio State University, Columbus 43210-1284.
The belief that high-carbohydrate diets enhance training capacity (mean power output) has been extrapolated from studies that have varied dietary carbohydrate over a few days and measured muscle glycogen but did not assess power output during training. We hypothesized that a high-carbohydrate (HI) diet (10 g.kg body mass-1.day-1) would promote greater muscle glycogen content and greater mean power output during training than a moderate-carbohydrate (MOD) diet (5 g.kg body mass-1.day-1) over 4 wk of intense twice-daily rowing training. Dietary protein intake was 2 g.kg body mass-1.day-1, and fat intake was adjusted to maintain body mass. Twelve male and 10 female collegiate rowers were randomly assigned to the treatment groups. Training was 40 min at 70% peak O2 consumption (VO2) (A.M.) and either three 2,500-m time trials to assess power output or interval training at 70-90% peak VO2 (P.M.). Mean daily training was 65 min at 70% peak VO2 and 38 min at greater than or equal to 90% peak VO2. Mean muscle glycogen content increased 65% in the HI group (P less than 0.05) but remained constant at 119 mmol/kg in the MOD group over the 4 wk. Mean power output in time trials increased 10.7 and 1.6% after 4 wk in the HI and MOD groups, respectively (P less than 0.05). We conclude that a diet with 10 g carbohydrate.kg body mass-1.day-1 promotes greater muscle glycogen content and greater power output during training than a diet containing 5 g carbohydrate.kg body mass-1.day-1 over 4 wk of intense twice-daily rowing training.(ABSTRACT TRUNCATED AT 250 WORDS)
Development of race profiles for the performance of a simulated 2000-m rowing
Kennedy MD, Bell GJ.
Faculty of Rehabilitation Medicine, E407 Van Vliet Center, University of Alberta, Edmonton, Alberta T6G 2H9, Canada.
The purpose of this study was to determine the race profile for a 2000-m simulated rowing race as well as the effect of training and gender on the race profile. Nineteen men and 19 women undertook a 2000-m simulated rowing race before and after 10 weeks of a typical off-season training program for rowing. Velocity was calculated every 200 m and the deviation in velocities from the mean race velocity (MRV) was plotted every 200 m to produce race profiles for each gender before and after training. The three fastest male rowers varied approximately 0.02 m.s from the MRV after training and displayed a constant-pace model. The fastest female rowers displayed an all-out strategy after training, producing large deviations from MRV. Average squared deviations from the mean (SDM) determined that all groups except the fastest females had a reduction in MRV deviation after training. These results suggest that the optimal race profile for a simulated 2000-m rowing race may be different between genders. Training reduces SDM and influences both male and female pacing patterns such that both exhibit a pacing strategy that is more similar to that of elite athletes in other events of similar and shorter duration.
Intra-abdominal pressure and rowing: the effects of inspiring versus expiring during the drive.
Manning TS, Plowman SA, Drake G, Looney MA, Ball TE.
Department of Kinesiology and Physical Education, Northern Illinois University, DeKalb 60115, USA.
BACKGROUND: The lumbar vertebrae of rowers are subjected to high levels of shear and compression at mid-drive, but intra-abdominal pressure (IAP) may partially neutralize these forces. IAP fluctuates with breathing. This study compared the IAP between inspiring during the drive and expiring during the drive. METHODS: Experimental design: ten volunteers performed one 5x2-minute repetition test while inspiring during the drive and one 5x2-minute repetition test while expiring during the drive on a rowing ergometer. The five work rates were: 100, 125, 150, 175 and 200 watts at 22, 24, 26, 28 and 30 strokes per minute, respectively. Measures: the movement of the body while rowing was analyzed using a position sensor, and IAP was measured using a pressure transducer catheter. RESULTS: A 2x5 repeated measures analysis of variance showed that there was a significant interaction for the dependent variable mid-drive IAP (p<0.05), with the mid-drive IAP increasing at a greater rate while expiring during the drive relative to inspiring during the drive. Across work rate, the mid-drive IAP and minimal IAP were significantly higher while expiring during the drive than inspiring during the drive (p<0.05). Across breathing pattern, the minimal IAP, maximal IAP, average change in IAP and mid-drive IAP increased significantly with work rate (p<0.05). CONCLUSIONS: The data show that expiring during the drive leads to a greater mid-drive IAP than inspiring during the drive.
Impact of two different body mass management strategies on repeat rowing performance.
Slater GJ, Rice AJ, Tanner R, Sharpe K, Jenkins D, Hahn AG.
Department of Physiology, Australian Institute of Sport, Belconnen, Australian Capital Territory, Australia. firstname.lastname@example.org
PURPOSE: The present study was conducted to examine the impact of acute weight loss on repeat 2000-m rowing ergometer performance during a simulated multiday regatta, and to compare two different body mass management strategies between races. METHODS: Competitive rowers (N = 16) were assigned to either a control (CON), partial recovery (REC(partial)), or complete recovery (REC(complete)) group. Volunteers completed four trials, each separated by 48 h. No weight restrictions were imposed for the first trial. Thereafter, athletes in REC(partial) and REC(complete) were required to reduce their body mass by 4% in the 24 h before trial 2, again reaching this body mass before the final two trials. No weight restrictions were imposed on CON. Aggressive nutritional recovery strategies were used in the 2 h following weigh-in for all athletes. These strategies were maintained for the 12-16 h following racing for REC(complete) with the aim of restoring at least three quarters of the original 4% body mass loss. Postrace recovery strategies were less aggressive in REC(partial); volunteers were encouraged to restore no more than half of their initial 4% body mass loss. RESULTS: Acute weight loss increased time to complete the first "at-weight" performance trial by a small margin (mean 3.0, 95% CI -0.3 to 6.3 s, P = 0.07) when compared with the CON response. This effect decreased when sustained for several days. Aggressive postrace recovery strategies tended to eliminate the effect of acute weight loss on subsequent performance. CONCLUSION: Acute weight loss resulted in a small performance compromise that was reduced or eliminated when repeated over several days. Athletes should be encouraged to maximize recovery in the 12-16 h following racing when attempting to optimize subsequent performance.
Inspiratory muscle training improves rowing performance.
Volianitis S, McConnell AK, Koutedakis Y, McNaughton L, Backx K, Jones DA.
School of Sport and Exercise Sciences, The University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom. email@example.com
PURPOSE: To investigate the effects of a period of resistive inspiratory muscle training (IMT) upon rowing performance. METHODS: Performance was appraised in 14 female competitive rowers at the commencement and after 11 wk of inspiratory muscle training on a rowing ergometer by using a 6-min all-out effort and a 5000-m trial. IMT consisted of 30 inspiratory efforts twice daily. Each effort required the subject to inspire against a resistance equivalent to 50% peak inspiratory mouth pressure (PImax) by using an inspiratory muscle training device. Seven of the rowers, who formed the placebo group, used the same device but performed 60 breaths once daily with an inspiratory resistance equivalent to 15% PImax. RESULTS: The inspiratory muscle strength of the training group increased by 44 +/- 25 cm H2O (45.3 +/- 29.7%) compared with only 6 +/- 11 cm H2O (5.3 +/- 9.8%) of the placebo group (P < 0.05 within and between groups). The distance covered in the 6-min all-out effort increased by 3.5 +/- 1.2% in the training group compared with 1.6 +/- 1.0% in the placebo group (P < 0.05). The time in the 5000-m trial decreased by 36 +/- 9 s (3.1 +/- 0.8%) in the training group compared with only 11 +/- 8 s (0.9 +/- 0.6%) in the placebo group (P < 0.05). Furthermore, the resistance of the training group to inspiratory muscle fatigue after the 6-min all-out effort was improved from an 11.2 +/- 4.3% deficit in PImax to only 3.0 +/- 1.6% (P < 0.05) pre- and post-intervention, respectively. CONCLUSIONS: IMT improves rowing performance on the 6-min all-out effort and the 5000-m trial.
The prediction of power and efficiency during near-maximal rowing.
Jensen RL, Freedson PS, Hamill J.
Department of Kinesiology, Health Promotion, and Recreation, University of North Texas, Denton 76203, USA.
The relationship between power and gross efficiency during near-maximal rowing, and physiological measures of strength, power, aerobic and anaerobic capacities and United State Rowing Association (USRA) performance tests (independent variables) was investigated among collegiate male rowers. Criterion measures of rowing power and gross efficiency were measured in a moving-water rowing tank, using an oar instrumented with strain gauges to assess force and a potentiometer to assess oar position. Bivariate correlation analysis (n = 28) indicated no relationship between the independent variables and rowing gross efficiency (P > 0.05). Rowing power [mean (SD) 483.4 (34.75) W] was significantly related to inboard leg extension strength (IL strength, r = 0.63), outboard leg extension strength (r = 0.45), combined leg extension strength (r = 0.45), and time to complete the USRA 2000-m simulated rowing race (r = -0.52; P <0.05). Stepwise regression using resampling cross-validation of 15 random samples (21 subjects per sample selected from a total group of 28 intercollegiate oarsmen) indicated that predictors of rowing power were IL strength and blood lactate following a peak oxygen uptake rowing test with significant multiple correlations of R 0.61 to 0.86 (P <0.05). The standard error of estimate (SEM) ranged from 18.1 to 29.9 W, or 5.3 (0.77) percent of the criterion value. Cross-validation with a hold-out group (seven subjects per sample) was performed for each equation and correlations ranged from R = 0.14 to 0.97 (SEM = 8.0 to 38.9 W). In conclusion, data from the present study suggest that to increase rowing power, training should emphasize leg strength and anaerobic training to decrease the level of lactate accumulated during rowing.
The effect of high-load vs. high-repetition training on endurance performance.
Ebben WP, Kindler AG, Chirdon KA, Jenkins NC, Polichnowski AJ, Ng AV.
Department of Physical Therapy, Marquette University, Milwaukee, Wisconsin 53201, USA. firstname.lastname@example.org
The purpose of this study was to compare the effects of high-load (H-load) periodized resistance training and high-repetition (H-rep) reverse step loading periodized resistance training on endurance performance. Twenty-six female university rowers (age = 20 +/- 1 year) were randomly assigned to H-load (5 novice, 8 varsity) or H-rep (7 novice, 6 varsity) groups. Subjects were pre- and posttested using a 2,000-m rowing ergometer test. Outcome variables included VO2 peak, time to test completion, total power, average power per stroke, total number of strokes, stroke rate, and body mass. Subjects trained for 8 weeks using identical exercises. Varsity rowers who performed H-load training demonstrated greater improvement compared with those who performed H-rep training. Novice rowers who performed H-rep training demonstrated greater improvement compared with those who performed H-load training. High-load periodized training appears to be more effective for athletes with advanced training status, and H-rep reverse step loading periodized training is more effective for those who are relatively untrained.
Isometric rowing strength of experienced and inexperienced oarsmen.
The significance of isometric muscle strength for rowing performance was studied. The questions investigated were: A) Is the isometric rowing strength (IRS) of oarsmen which is two to three times the dynamic force applied on the oar at maximal power rowing, a ratio which is equivalent to the maximal efficiency of Hill's force/velocity relationship? B) Is IRS higher among successful oarsmen that among those less so? C) Is isometric strength of individual muscle groups correlated to IRS? From measurments on 40 oarsmen the results showed: a) IRS among the most successful oarsmen was 2.6 times the dynamic force indicated in literature; b) IRS was 21 kp higher in the 7 international competitive oarsmen than in 22 national oarsmen, and 42 kp higher than IRS of 11 club oarsmen; and c) of eight other strength determinations only hand grip strength was correlated to IRS. It is suggested that IRS, but not isometric strength of individual muscle groups limits rowing performance.
The effect of velocity-specific strength training on peak torque and anaerobic rowing power.
Bell GJ, Petersen SR, Quinney HA, Wenger HA.
Department of Physical Education and Sport Studies, University of Alberta, Edmonton, Canada.
This study investigated the effect of low- and high-velocity resistance training on isokinetic peak torque and anaerobic power output. Eighteen male varsity oarsmen were blocked on peak knee extension torque at 3.14 rad s-1 and assigned to a high-velocity resistance training group (HVR), a low-velocity resistance training group (LVR) or a control group. Subjects trained four times a week for 5 weeks. Each training session included three circuits of 12 stations using variable-resistance hydraulic equipment. The HVR training significantly improved peak torque (P less than 0.05) in knee extension and flexion at 2.61, 3.14, 3.66 and 4.19 rad s-1. The LVR training produced significant improvements (P less than 0.05) in peak torque for knee extension and flexion at 0.52, 1.05, 1.57 and 2.61 rad s-1. High positive correlations were found between peak torque and anaerobic power outputs for all groups. However, no significant changes occurred in 15 s power output, average 90 s power output or peak blood lactate in either training group. These results indicate that velocity-specific strength training does not necessarily improve anaerobic power output in a different exercise mode despite the high positive correlation between isokinetic strength and anaerobic power output.
Technique and muscle force.
In the sport of rowing, as may be the case in other sports, the coach frequently tends to relate to skills or technical movement in terms of their aesthetic appearance rather than to their kinesiological requirements, or muscular effectiveness. Maximal isometric strength was tested (N = 18) in three components of the rowing stroke: height of sagittal pull; angle of pull in sagittal plane; and the power position in both the catch and the finish. The results of this investigation suggest that certain technical parameters commonly utilized by rowing coaches seem to be less efficient when discussing muscular effectiveness. Thus one might conclude, that slight alterations in the cycle of the rowing stroke are desirable.
Electromyographic analysis of rowing stroke biomechanics.
Rodriguez RJ, Rogriguez RP, Cook SD, Sandborn PM.
Department of Orthopaedic Surgery, Tulane University School of Medicine, New Orleans, Louisiana.
Electromyography was used to study muscle activity in the upper and lower extremities and torso during the rowing stroke. Five experienced male rowers were tested while rowing on a Concept II ergometer. In order to fully evaluate the rowing stroke, six phases were utilized to identify the transition points where individual muscles become more active due to body angle or nature of the motion. The results indicate that the strength of an individual muscle is most likely not as important to the rowing stroke as the combined activity of two or more groups of muscles. Thus, in addition to strength, it is of great value to the oarsman to develop technical skill to coordinate his upper and lower body reactions.
Electromyographic validation of basic exercises for physical conditioning programmes. III. Influence of the grip in the capacity of the rowing exercises in determining action potential levels for the deltoid and the pectoralis major muscle.
Ferreira MI, Bull ML, Vitti M.
Department of Anatomy, State University of Rio de Janeiro, Brasil.
The electromyographic activity of the shoulder muscles Deltoid--anterior portion (DA) and Pectoralis major--clavicular portion (PMC) was tested on 24 male volunteers using a 2 channel TECA TE4 electromyograph and Hewlett Packard surface electrodes during the execution of three different modalities of rowing exercises comparing middle grip with closed grip. Statistical comparisons showed that in both PMC and DA closed grip determined muscular solicitation higher than middlegrip excepting sitting rowing. The authors present some suggestions to the use of the tested exercises.
An analysis of the pacing strategy adopted by elite competitors in 2000 m rowing.
English Institute of Sport, Baltic Business Centre, Saltmeadows Road, Gateshead, Tyne & Wear NE8 3DA, UK. email@example.com
OBJECTIVES: To determine the pacing strategies adopted by elite rowers in championship 2000 m races. METHODS: Split times were obtained for each boat in every heavyweight race of the Olympic Games in 2000 and World Championships in 2001 and 2002, and the top 170 competitors in the British Indoor Rowing Championships in 2001 and 2002. Data were only included in subsequent analysis if there was good evidence that the athlete or crew completed the race in the fastest possible time. The remaining data were grouped to determine if there were different strategies adopted for on-water versus ergometer trials, "winners" versus "losers", and men versus women. RESULTS: Of the 1612 on-water race profiles considered, 948 fitted the inclusion criteria. There were no differences in pacing profile between winners and losers, and men and women, although on-water and ergometry trials showed a competitively meaningful significant difference over the first 500 m sector. The average profile showed that rowers performed the first 500 m of the race faster than subsequent sectors-that is, at a speed of 103.3% of the average speed for the whole race, with subsequent sectors rowed at 99.0%, 98.3%, and 99.7% of average speed for on-water rowing, and 101.5%, 99.8%, 99.0%, and 99.7% for ergometry. CONCLUSIONS: These data indicate that all athletes or crews adopted a similar fast start strategy regardless of finishing position or sex, although the exact pace profile was dependent on rowing mode. This strategy should be considered by participants in 2000 m rowing competitions.
Impact of acute weight loss and/or thermal stress on rowing ergometer performance.
Slater GJ, Rice AJ, Sharpe K, Tanner R, Jenkins D, Gore CJ, Hahn AG.
Department of Physiology, Australian Institute of Sport, Belconnen, Australian Capital Territory, Australia. firstname.lastname@example.org
PURPOSE: The impact of acute weight loss on rowing performance was assessed when generous nutrient intake was provided in 2 h of recovery after making weight. METHODS: Competitive rowers (N = 17) completed four ergometer trials, each separated by 48 h. Two trials were performed after a 4% body mass loss in the previous 24 h (WT) and two were performed after no weight restrictions, that is, unrestricted (UNR). In addition, two trials (1 x WT, 1 x UNR) were in a thermoneutral environment (NEUTRAL, mean 21.1 +/- SD 0.7 degrees C, 29.0 +/- 4.5% RH) and two were in the heat (HOT 32.4, +/- 0.4 degrees C, 60.4 +/- 2.7% RH). Trials were performed in a counterbalanced fashion according to a Latin square design. Aggressive nutritional recovery strategies (WT 2.3 g x kg(-1) carbohydrate, 34 mg x kg(-1) Na, 28.4 mL x kg(-1) fluid; UNR ad libitum) were employed in the 2 h after weigh-in. RESULTS: Both WT (mean 2.1, 95% CI 0.7-3.4 s; P = 0.003) and HOT (4.1, 2.7 - 5.4 s; P < 0.001) compromised 2000-m time-trial performance. Whereas WT resulted in hypohydration, the associated reduction in plasma volume explained only part of the performance compromise observed (0.2 s for every 1% decrement) Moreover, WT did not influence core temperature or indices of cardiovascular function. CONCLUSIONS: Acute weight loss compromised performance, despite generous nutrient intake in recovery, although the effect was small. Performance decrements were further exacerbated when exercise was performed in the heat.
Training of rowers before world championships.
Steinacker JM, Lormes W, Lehmann M, Altenburg D.
Abteilung Sport- und Leistungsmedizin, Universitat Ulm, Germany. email@example.com
In rowing, static and dynamic work of approximately 70% of the body's muscle mass is involved for 5.5 to 8 min at an average power of 450 to 550 W. In high load training phases before World Championships, training volume reaches 190 min.d-1, of which between 55 and 65% is performed as rowing, and the rest is nonspecific training like gymnastics and stretching and semispecific training like power training. Rowing training is mainly performed as endurance training, rowing 120 to 150 km or 12 h.wk-1. Rowing at higher intensities is performed between 4 and 10% of the total rowed time. The increase in training volume during the last years of about 20% was mainly reached by increasing nonspecific and semispecific training. The critical borderline to long-term overtraining in adapted athletes seems to be 2 to 3 wk of intensified prolonged training of about 3 h.d-1. Sufficient regeneration is required to avoid overtraining syndrome. The training principles of cross training, alternating hard and easy training days, and rest days reduce the risk of an overtraining syndrome in rowers.