Understanding Workout Fatigue

Posted by Scott Christensen



How long do your middle distance athletes need to rest after a workout?

Understanding workout fatigue – How long do your middle distance athletes need to rest during a workout?

In the 1950’s a pioneering German in athletics by the name of Woldemar Gerschler worked as a physical educator, track and field coach, and Director of the Freiburg Institute for Physical Education.  He is considered the father of interval training. Gerschler was certainly the first to organize training into a systematic organization of all the components that endurance coaches use today. He used extensive physical and psychological tests to help guide and advise his runners. Gerschler and his colleagues Herbert Reindel, a medical doctor and physiologist and Helmutt Roskamm authored a definitive work, Das Intervall-training, published by Barth publishers, Munich, in 1962.  His system was focused on cardiac physiology and the adaptations that could be made in training the heart. The system was based on three principles: 1) Exercise increases heart rate and rest slows it down. 2) Repeated physical exercise will slow heart rate while pumping the same volume of blood. 3) The volume of blood for each individual is constant. Based on his work with Dr Herbert Reindel they developed the Gerschler-Reindel Law. So, in understanding workout fatigue, they found from their experiments that the heart rate in their subjects did not surpass 180 BPM; and that represented the upper limit of intense work. They then allowed the subjects 90 seconds to return to 120 -125 BPM and then the next bout of work could commence.  They termed this “the worthwhile break”, or what we now call an “interval”.

If it took longer then that to return to 125 BPM, because the effort was too hard or too long, then they lengthened the rest interval. Gerschler felt is was the recovery that strengthened the heart. He felt that there was a strong stimulus of the stroke volume immediately after the beginning of the recovery phase, so the recovery became a big focus hence the name interval training. The recovery was a walk in the beginning stages and then a jog as the runner gained fitness.  Their research showed that 21 days of constant interval training at maximum effort will produce a 20% increase in blood volume pumped during a single contraction.

Need help analyzing your mid distance athletes post competition? Read Performance Comparison in Endurance Athletes

According to research published by the Gerschler-Reindel training group, they determined that that during the first one-third of rest interval required for full recovery, two-thirds of the recovery takes places.  This is the guideline that coaches use today in setting up appropriate rest intervals for their middle distance athletes.  The workout scheme then depends on the desired physiological adaptations in concert with the training concepts listed below.

1.   In Anaerobic Training

  • Intensity for anaerobic work exceeds 90% of maximum velocity
  • Recovery requires more time between both repetitions and sets than recovery between aerobic stimuli.

2.   In Aerobic Training

  • The interval between each aerobic stimulus is normally between 1 and 2 times the running time (1-2 x RT) of each repetition.

3.   Complete Recovery

  • A return to near pre-exercise heart rate or homeostasis.

4.   Incomplete Recovery

  • After one third of the time required for full recovery (HR 120-130 bpm).

5.   Recovery Techniques

  • The methods to aid in recovery between repetitions such as walking and jogging are more effective than a passive inactive recovery (Figure 1).

Figure 1.  The differences in athlete recovery from a very hard bout of anaerobic work are shown.  The graph indicates differences between active and passive athlete recovery.

Often middle distance coaches become set on the length of a rest interval and use it throughout the season no matter what the anaerobic workout is.  As Figure 1 indicates, the bodies system will continue to accumulate lactate (measurable indicator of lactic acid) for about 30 seconds after the work has ended.  At about the three minute recovery mark, the difference in recovery between the active and passive athlete is most dramatic.  At the twelve minute mark the recovery is identical.  If the rest period exceeds twelve minutes, then it does no matter how the athlete recovers from the bout of work.

As a middle distance coach do not get locked into set rest intervals while doing Speed Endurance, Special Endurance 1, or Special Endurance 2 work.  Determine the training effect that you want the athlete to achieve and set the interval of rest accordingly for best results.

More Middle Distance Training: Preparation of the Elite Junior Middle Distance Runner



Scott Christensen - Scott Christensen’s teams have been ranked in the national top 10 eight times. He won the 1997 High School National Championship and his squads have captured multiple Minnesota State Championships. Scott has coached 13 Minnesota State Championship-winning teams and 27 individual Minnesota State Champions. He was the USTFCCCA Endurance Specialist School junior team leader for the World Cross Country Team in 2003 and the senior team leader in 2008. Scott is a 14-year USATF Level II endurance lead instructor.

Related Posts

Quantifying Training Effort of Middle Distance Runners

Training Aerobic Capacity and Middle Distance Athletes

Advanced Warmup Routines for Middle Distance Athletes

An Endurance Training Session for Middle Distance Athletes

Intensity – Can It Be Too Much In Middle Distance Training?