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.
Figure 4. Easy running on paved road on the other hand is much less demanding
because there is minimal variance between steps cycles. The exercise intensity stays
well inside target zone (green).
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 5. MFT test and determined zones. NOTE! This specific data includes short
stops between intensities to collect blood samples during our validation process.
The common problem with young athletes and especially among speed and power
athletes is that they tend to overspeed during low intensity sessions. Therefore, the
exercises that are targeted to improve basic endurance enhance speed endurance instead.
Therefore, monitoring the exercise intensity is crucial for them.
Figure 6 presents warm-up from this young middle distance runner. It can be seen, that
the intensity in the beginning, first 5 minutes, is too high (yellow zone), but by
decreasing the running speed he can return to basic endurance level (green zone).
However, the running speed during warm-up could be even lower.
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