In the previous two articles we presented Myontec’s muscle fatigue threshold (MFT)
analysis and training zones derived from it. Now we will go through how these zones
can be used in practise and what benefit they bring.
1. Orienteer: Light training during rehabilitation The athlete is world-class orienteer who is in rehabilitation phase after injury. He had performed incremental running test 6 x 1000 m from which the MFT and corresponding zones were determined. Figure 1 shows average muscle activation during test as well as determined MFT and corresponding zones.
Figure 1. MFT test and determined zones.
During rehabilitation, the training target was to perform easy basic endurance running sessions that would not fatigue and overuse the injured leg. In the following figures different data samples during training period are presented.
Figure 2. Easy running on dirty trail. Dirty in this case means that trail includes some obstacles on ground e.g. rocks, sticks, leaves, that need to be taken into account during running. Trails also typically include more turns and mounds as compared to roads and therefore activation has variance. However, the intensity stays nicely within the basic endurance zones (blue & green).
Figure 3. Orienteering in forest. Training load remains nicely within basic endurance zones (blue & green). However, activation is wavy due to uneven surface and constant variance in steps which present huge demands to nervous system to control balance and coordinate running through obstacles on ground.
2. Middle distance runner Another example we give is a young middle distance runner. He also run incremental 6 x 1000 m running test which is shown in figure 5.
Figure 6. 15 minutes aerobic (jogging) warm-up.
Figure 7 shows 2 x 8 x 150 m speed endurance training session. During sprints the exercise intensity exceeds the MFT threshold dramatically (red zone). That is because fast twitch muscle fibres have huge potential to force production but majority of them are recruited only at maximal intensity. Fast twitch fibres get also fatigued fast and therefore their force potential is the best used during fast sprints and they need time to
recover after these spurts.
Figure 7. 2 x 8 x 150 m speed endurance training session with 100 s rest between reps and 4 min rest between sets. High peaks are 150 m sprints and lower valleys between them are walking back to start line during rest. Note the increase in resting (walking) activation especially after 10 reps (from blue to green zone). Thereafter fatigue starts to accumulate with increasing speed (rise of maximum peaks in red zone).
We hope that we have proven that muscle activation can be used to monitor exercise intensity. Activation information during training serves as a training diary to record daily, weekly and monthly loading intensities. Muscle activation responds quickly to changes in intensity as well as in technique. Also fatigue in working muscles can be spotted in real-time. In addition to exercise intensity the muscle balance and relaxation level that are essential information for safe training, can be monitored simultaneously. Therefore, is it quite safe to say that monitoring muscle activity during training offers substantial benefits to optimize training. We’ll continue posting more practical examples related to the muscular zones.
Authors: Pekka Tolvanen, M.Sc. (Physics), Product Manager, Founder of Myontec Merja Hoffrén-Mikkola, PhD (biomechanics), Content Developer, Myontec