Jorn Trommelen, PhD
@jorntrommelen.bsky.social
Assistant professor. Muscle Metabolism.
Follow @jorntrommelen.bsky.social for more evidence-based threads on exercise, nutrition and metabolism.
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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
✅ 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 10:34 AM
Follow @jorntrommelen.bsky.social for more evidence-based threads on exercise, nutrition and metabolism.
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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
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
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
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
A limitation is that muscle protein breakdown was not measured, even though it may also increase with a higher training volume.
10/11
10/11
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
10/11
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
9/11
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
9/11
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
8/11
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
8/11
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
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
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
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
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
• 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
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
• 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
MPS was measured in the early phase (first 5 hours post-exercise) and the next day (24-29 hours postexercise).
5/11
5/11
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
5/11
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
• 1 set unilateral leg extensions to failure
• 3 sets of unilateral leg extensions to failure
4/11
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
• 1 set unilateral leg extensions to failure
• 3 sets of unilateral leg extensions to failure
4/11
This study investigated the effect of resistance exercise volume on muscle protein synthesis (MPS; the process driving muscle adaptations such as growth).
3/11
3/11
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
3/11
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
Others have suggested that more sets always produce more gains.
2/11
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
Others have suggested that more sets always produce more gains.
2/11
November 21, 2025 at 2:10 PM
10/10 - Thank you to all the collaborators & participants who made this project possible. Follow @jorntrommelen for more evidence-based threads on exercise, nutrition & metabolism. Please like & share the first tweet linked below to help spread the word:
bsky.app/profile/jorn...
bsky.app/profile/jorn...
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)
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
10/10 - Thank you to all the collaborators & participants who made this project possible. Follow @jorntrommelen for more evidence-based threads on exercise, nutrition & metabolism. Please like & share the first tweet linked below to help spread the word:
bsky.app/profile/jorn...
bsky.app/profile/jorn...
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
Open-access link:
journals.humankinetics.com/view/journal...
9/10
November 21, 2025 at 2:08 PM
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
Open-access link:
journals.humankinetics.com/view/journal...
9/10
Limitations were that single-leg cycling does not reflect real-world training and that habitual physical activity was not controlled.
8/10
8/10
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
8/10
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
7/10
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
7/10
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
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
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
This aligns with long-term studies showing minimal impact of endurance exercise intensity on gains in fat-free mass.
6/10
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
• 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
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
• 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
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
4/10
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
4/10
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
Myofibrillar protein synthesis rates were assessed, reflecting the synthesis of muscle contractile proteins.
3/10
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
Myofibrillar protein synthesis rates were assessed, reflecting the synthesis of muscle contractile proteins.
3/10
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
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
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
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
Follow me @jorntrommelen for more evidence-based threads on exercise & nutrition.
If you think others would benefit too, please like & repost the first tweet linked below.
bsky.app/profile/jorn...
If you think others would benefit too, please like & repost the first tweet linked below.
bsky.app/profile/jorn...
Motivation is not enough, make a concrete plan!
Exercise participation and:
- Impact of education?
- Impact of concrete planning?
Let’s break it down!
1/x
Exercise participation and:
- Impact of education?
- Impact of concrete planning?
Let’s break it down!
1/x
November 13, 2025 at 3:40 PM
Follow me @jorntrommelen for more evidence-based threads on exercise & nutrition.
If you think others would benefit too, please like & repost the first tweet linked below.
bsky.app/profile/jorn...
If you think others would benefit too, please like & repost the first tweet linked below.
bsky.app/profile/jorn...
In conclusion, education about the health benefits of exercise alone increases motivation but may not increase exercise participation. Adding a concrete plan specifying what, when, and where to exercise substantially increases participation.
Study:
www.ncbi.nlm.nih.gov/pubmed/14596...
10/10
Study:
www.ncbi.nlm.nih.gov/pubmed/14596...
10/10
Combining motivational and volitional interventions to promote exercise participation: protection motivation theory and implementation intentions - PubMed
It is concluded that supplementing PMT with implementation intentions strengthens the ability of the model to explain behaviour. This has implications for health education programmes, which should aim to increase both participants' motivation and their volition.
www.ncbi.nlm.nih.gov
November 13, 2025 at 3:40 PM
In conclusion, education about the health benefits of exercise alone increases motivation but may not increase exercise participation. Adding a concrete plan specifying what, when, and where to exercise substantially increases participation.
Study:
www.ncbi.nlm.nih.gov/pubmed/14596...
10/10
Study:
www.ncbi.nlm.nih.gov/pubmed/14596...
10/10