JARA Coach Seminar 98 / Kurt Jensen

[Ozawa Rowing Top Page] [Seminar Library INDEX] update:1998-12-11


Sponsorship: Japan Rowing Association
Date and Place :1998.12.5/Toda, Tokyo 1998.12.6/Seta, Shiga

Power-endurance relationship in ergometer rowing and it's use in the definition of training intensities

By Kurt Jensen, Team Danmarks Testcenter, Institute of physical Education and Sport science, Odense University, Denmark

Introduction
Rowing in the northern part of Europe can be difficult during winter season due to ice on the water, shorter daylight periods and bad weather conditions. Consequently, other training forms like crosss-country skiing, running, cycling, circuit training etc. have been applied. However, in Denmark, during the last decade, ergometer rowing has been more and more popular in periods when rowing otherwise is not possible on the water. The following paper will give an example of how ergometer rowing has been used in the definition of individual training intensitiies and training models in ergometer rowing and in the boat.

Training
Training for rowing competitions is performed within intensities ranging from 60 to well above 100% of maximal oxygen uptake (VO2max). Training intensities can be defined according to the expected effects on the metabolic energy systems(Ref.1); anaerobic (BL above 6 mmol/l), aerobic transportation (4-6 mmol/l), anaerobic threshold (4 mmol/l) and aerobic utilization 1 and 2 (2-4 and below 2 mmol/l), respectively. During training in a boat, the intensity is usually controlled by stroke rate, boat speed or heart rate measurements. To identify intensity levels for training also lactate concentration has been used(2). Yet, the ultimate way in expressing intensity is to measure the force on the oar handle and the corresponding time for each stroke during training or to calclate the corresponding work and power performed. For practical reasons these applicaions are still not available, in general. However. during rowing in a rowing ergometer the power is measured continuously. Average power produced during "all-out" performances over fixed times or distances in a rowing ergometer can be plotted to establish a so-called power-endurance curve, which can be used as a tool for a precise definition of training intensity. During rowing in an ergometer, the work load in watt can be applied directly, and the "learning" of being on a given intensity in an ergometer can then be transferred when rowing in the boat.

Material and methods
Nine Danish senior B oarsmen from a local training centre - five open class and four lightweights- participated in the study (Tab 1). During the last week in November- at the beggining of the winter season - a range of performance tests were carried out on a rowing ergometer (Tab 2). Two weeks after the field test, a laboratory test for measurement of maximal oxygen uptake (VO2max) and estimation of W4 and W6 were performed according to the standard procedure described previously(3).

Results
The average power in the group ranged from 284 (236-319) watt during 1 hour all-out rowing to 741 (551-948) watt during 10 sec all-out (Tab 3, Fig 1). The critical power was calculated as the slope of the linear regression line between working times and work(J) in the field test to be 278 (232-312) watt. The work intensity during the submaximal rowing ergometer test, that increased the blood lactate concentration to 4 and 6 mmol/l (W4 and W6) was estimated to be 303 (250-350) and 330 (267-379) watt (Fig 1). W4 and W6 are included on Fig 1 indicating that these work intensities can be used for training up to approximately 44 and 22 min, respectively.

Applications
The power-endurance curve was used for definition of different levels for work intensities in the rowing training A, B, C, D and E (Fig 3). Each rower used his own power-endurance curve to define individual training intensities. Training intensities for rowing were defined as follows: A:110-180%, B:90-105%, C:75-85% and D:65-70% of power at race pace. The 2 km time trial at race pace were considered to be 100%. The corresponding stroke and heart rates were: 36-40, 30-36, 26-30, and 22-26 strokes per minute and 0, 0-10, 10-20, and 20-40 beats per minute below maximal heart rate for level A to D, respectively. During training, the rowers were encouraged to be aware of the subjective feeling of being at a given intensity level. The power-endurance curve indicates for how long time it is possible to sustain a given work load. For instance work loads at level C can maximally be sustained once for 20-60 min. A typical training model in C could therefore be 12 km as fast as possible or alternatively two times 6km separated by 10-20 min recovery. The heart rate should be 10-20 beats below maximum - slightly increasing throughout the work interval and the stroke rate 26-28 (small boats) or 28-30 (bigger boats). Level D is for continuous rowing for minimum one hour, or may be up two hours only varying the stroke rate slightly. A typical training model could be 30+20+10+10 min at 22, 24, 22 and 26 strokes per min, heart rate 20-40 beats below maximal - slightly increasing throughout the work. Lower intensities should only be used for recovery or specific technical purposes or for very long endurance training (several hours). Regarded the two highest intensity levels A and B, training is carried out as bouts of interval training to keep the intensity sufficient high in each bout. The work time in each bout should be relatively short to be able keep the right intensity - e.g. not longer than 10 min and 2 min in B and A, respectively. The recovery time between bouts should be at least half of work time in the longer intervals (8-10 min) and up to five times the work interval during short intervals (10-30 sec). Examples of typical training models and the description of work load are included in table 4 and 5. Furthermore a typical training week in the mid season the week before a competition is included (Table 6).

Summery
The purpose of the present study was to evaluate the performance in a group of Danish elite rowers in order to be able to define individual training intensities. Heart rate and blood lactate concentrations (BL) were deternmined while rowing 5 min at 240, 270, 300, 330 and 360 watt with a stroke rate of 22, 24, 26, 28 and 30 strokes per min, respectively. The work load and heart rate which increased BL to 4 and 6 mmol/l (W4, W6) were calclated using linear interpolation. Furthermore "all-out" performance tests were carried out at various work times; 10 and 60 sec, 2 and 6 km and 1 hour. All tests were performed within one week on a Concept IIC rowing ergometer. The average power during each test was plotted against time in a so-called power-endurance curve indicating a physical performance profile of the rowers. Included on the curve are W4 and W6, reflecting an average work time of 22 and 44 min. The 2 km trial at race pace were considerd to be 100% (see fig 1). Training intensities for rowing were defined as follows: A;110-180%, B:90-105%, C:75-85% and D:65-70% of power at race pace. The corresponding stroke and heart rates were: 36-40, 30-36, 26-30, and 22-26 strokes per minute and 0, 0-10, 10-20, and 20-40 beats per minute below maximal heart rate for level A to D, respectively. During training, the rowers were encouraged to be aware of the subjective feeling of being at a given intensity level. It is concluded, that a range of simple performance tests can be used as a reference for a definition of training intensities for rowing in an ergometer or a boat.

References
1. Jensen K, Nielsen TS,Smith M, Analyses of the Italian National Training Program for Rowing. FISA Coach 1990; 1; 2; 1-5
2. Hartmann U, A Mader, W Hollmann. Heart Rate and Lactate During Endurance Training Programs in Rowing and its Relation to the Duration of Exercise by Top Elite Rowers, FISA COACH 1990 1; 1; 1-4
3. Jensen K, Test procedures for rowing. FISA COACH 1994; 5; 4; 1-6

Text to figures
Fig 1. Power against work time in "all-out" test; 10 and 60 sec, 2 and 6 km and 1 hour. Included are W4 and W6 estimated from the laboratory test.
Fig 2. Submaximal and maximal work loads and the corresponding stroke and heart rate and blood lactate concentration during the laboratory test.
Fig 3. The definition of work levels in rerlation to the power-endurance curve


Translation to JAPANESE by Ozawa
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