Why does strength increase at the start of a training program?
Strength gains at the beginning of a strength training program are primarily due to coordination adaptations – not increased muscle mass or voluntary activation.
- Coordination: Fast and task-specific adaptation where the nervous system learns to perform a specific exercise more efficiently.
- Voluntary activation: The ability to recruit high-threshold motor units and stimulate more muscle fibers. This happens more slowly.
If strength gains were due to voluntary activation or muscle mass, you should see an increase in other exercises that use the same muscle group – but this doesn’t happen initially when introducing a completely new exercise. This is clearly seen in studies where strength only increases in the specific exercise being trained. Ansdell, P. et al. (2020).
Methodology
The study investigated the effect of 4 weeks of squat training on strength and muscle activity:
- Protocol: 3 sets x 8 repetitions, 3 times a week.
- Measurements:
- Isometric squat test (strength).
- Knee extension test (strength in another exercise).
- Muscle thickness via ultrasound (to assess muscle mass).
Study population
- 18 young, untrained people (10 in training group, 8 in control group).
- All were physically active but had no experience with systematic lower body strength training.
Interpretation of the study
- Squat strength increased by 35% after 4 weeks.
- Knee extension strength did not change (only 1% increase).
- No increase in muscle mass was observed.
Conclusion: The rapid strength gains are due to coordination adaptations and not muscle growth or improved voluntary activation.
Considerations as a bodybuilder
- Rapid strength gains ≠ bigger muscles
- At the start of a new exercise, progress is often neurological. The body learns to coordinate the movement better.
- Don’t change exercises too often to chase this “fast progress”. This is false progression! (not the desired increase in muscle mass)
- Exercise-specific strength
- Strength is task specific. An increase in squat does not mean strength gains in knee extensions.
- Powerlifters: Track your competition lifts to see if your accessory variations provide carry over.
- Focus on consistency in new exercises
- In the beginning: Learn the technique and focus on consistent training.
- After a few sessions, muscle growth and voluntary activation will take over as the primary adaptations.
- However, how quickly adaptations such as hypertrophy and increases in voluntary activation become primary adaptations for strength gains will depend on the complexity of the exercise and how quick you are to adopt to the demands of the exercise.
- High levels of voluntary activation are needed to stimulate higher voluntary activation, which is why it does not occur as long as coordination is still the primary adaptation that occurs. Jenkins et al (2017).
- Hypertrophy can be achieved while coordination-adaptation still occurs, but will not be maximized as we do not benefit from the right recruitment (stimulation of the more glycolytic fibers, which have the greatest growth potential).
How long does coordination last as a primary adaptation?
- High stability isolation exercises: Coordination adaptations happen quickly – often after 1-2 training sessions(Green et al., 2013).
- Complex multi-joint exercises: Coordination can take longer. In the squat, it took 12 sessions for untrained individuals, not knowing if coordination-adaptation was fully maxed out. (Ansdell et al., 2020).
What determines the duration?
- Exercise complexity: The more complex the exercise, the longer it takes to achieve coordination.
- Training experience: A trained person who has done similar movements will adapt faster.
Convenient takeaway
- In powerlifting, competition lifts are used as a measure of progress.
- SBD as a goal: Use the increase of your COMP. lift as a proxy for whether the other accessories have good carry over to your COMP. lift. When introducing a new variation, there will be an increase in strength due to coordination improvements, but it only matters if it increases your COMP. lift, so track your COMP. lift
- Avoid too much variation in complex exercises. You will see rapid progress in the desired exercises yes, but it will be from coordination, and not necessarily from hypertrophy or increase in voluntary activation.
- Remain consistent and let muscle growth and voluntary activation take over once coordination adaptation is achieved.