Jorn Trommelen, PhD
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jorntrommelen.bsky.social
Jorn Trommelen, PhD
@jorntrommelen.bsky.social
Assistant professor. Muscle Metabolism.
In conclusion:

a greater resistance exercise volume results in a higher and more prolonged stimulation of muscle protein synthesis.

Link to study:
pubmed.ncbi.nlm.nih.gov/20581041/

11/11
December 9, 2025 at 10:33 AM
A limitation is that muscle protein breakdown was not measured, even though it may also increase with a higher training volume.

10/11
December 9, 2025 at 10:33 AM
A strength of this work is the unilateral study design, which enables a direct within-participant comparison of 1 vs 3 sets, thereby minimizing influences of genetic and motivational factors.

9/11
December 9, 2025 at 10:33 AM
This suggests that resistance training volume (number of sets) is an important driver for muscle growth and that very low volumes may be suboptimal.

8/11
December 9, 2025 at 10:33 AM
Interpretation?

Even a single set of resistance exercise results in a clear increase in MPS.

However, three sets elicit a greater and longer-lasting MPS response.

7/11
December 9, 2025 at 10:33 AM
Key findings:
• Three sets produced a greater rise in early-phase MPS than one set.
• The next day, MPS remained elevated in the three-set treatment, whereas it had returned to baseline in the one-set treatment.

6/11
December 9, 2025 at 10:33 AM
MPS was measured in the early phase (first 5 hours post-exercise) and the next day (24-29 hours postexercise).

5/11
December 9, 2025 at 10:33 AM
Resistance-trained males performed a unilateral exercise protocol in which each leg completed a different condition, randomly assigned to:
• 1 set unilateral leg extensions to failure
• 3 sets of unilateral leg extensions to failure

4/11
December 9, 2025 at 10:33 AM
This study investigated the effect of resistance exercise volume on muscle protein synthesis (MPS; the process driving muscle adaptations such as growth).

3/11
December 9, 2025 at 10:33 AM
Some training philosophies, such as High-Intensity Training (HIT), propose that one set taken to failure is enough to maximize muscle growth.

Others have suggested that more sets always produce more gains.

2/11
December 9, 2025 at 10:33 AM
Does a higher resistance exercise volume stimulate MPS more?

✅ 1 set vs 3 sets
✅ Early vs late MPS
✅ Within-subject design

Let’s break it down!

1/11

@mackinprof.bsky.social
December 9, 2025 at 10:33 AM
In conclusion, high-intensity interval training does not enhance myofibrillar protein synthesis rates when compared to volume- and duration-matched moderate intensity continuous exercise.

Open-access link:
journals.humankinetics.com/view/journal...

9/10
November 21, 2025 at 2:08 PM
Limitations were that single-leg cycling does not reflect real-world training and that habitual physical activity was not controlled.

8/10
November 21, 2025 at 2:08 PM
A major strength was the one-leg within-subject design with volume- and duration-matched protocols, which allowed a clean comparison of exercise intensity.

7/10
November 21, 2025 at 2:08 PM
These findings suggest that even higher-intensity endurance exercise is not a strong stimulus for muscle protein synthesis.

This aligns with long-term studies showing minimal impact of endurance exercise intensity on gains in fat-free mass.

6/10
November 21, 2025 at 2:08 PM
Key findings:
• Single-leg maximal workload and VO2peak improved with both HIIT and MICT.
• Myofibrillar protein synthesis did not differ between HIIT, MICT, or the control period.

5/10
November 21, 2025 at 2:08 PM
Each of the ten subjects trained one leg with HIIT and the other with MICT, with both protocols matched for total volume and duration.

4/10
November 21, 2025 at 2:08 PM
We compared High-Intensity Interval Training (HIIT) and Moderate Intensity Continuous Training (MICT) over two weeks.

Myofibrillar protein synthesis rates were assessed, reflecting the synthesis of muscle contractile proteins.

3/10
November 21, 2025 at 2:08 PM
Endurance training improves oxygen uptake and mitochondrial function.

Interval training is often promoted as a time-efficient alternative to steady continuous cardio, and some claim it might even stimulate more muscle growth.

2/10
November 21, 2025 at 2:08 PM
Does interval training boost muscle protein synthesis more than continuous exercise?

HIIT vs MICT
✅ Within-participant design
✅ Unilateral cycling model
✅ MPS over 2 weeks

Let’s break it down (1/10)
November 21, 2025 at 2:08 PM
A strength of the study was the large sample size. Limitations include the very short study duration (1 week) and the outcome was based on self-reported session (not objectively verified).

9/x
November 13, 2025 at 3:40 PM
Creating a specific plan such as deciding what, when and where to exercise, can help turn intentions into action. This strategy, known as implementation intentions, has been shown to work for other behaviors as well.

8/x
November 13, 2025 at 3:39 PM
Interpretation:
This study shows that information alone can increase motivation, but that this does not always lead to behavior change. Even motivated individuals may fail to act.

7/x
November 13, 2025 at 3:39 PM
Key finding (2/2):
- Education combined with a planning task increased both motivation and actual exercise participation (91% of participants exercised at least once in the week following the intervention).

6/x
November 13, 2025 at 3:39 PM
Key finding (1/2):
- Education alone increased the motivation to exercise but did not increase actual exercise participation; many participants reported being ‘too busy to exercise’.

5/x
November 13, 2025 at 3:39 PM