In untrained young men, one session of weight lifting raises the production of muscle structural proteins by 67% and energy-producing mitochondrial proteins by 69%, while one session of running raises mitochondrial protein production by 154% but does not change muscle structural protein production.
See the scientific wording
In untrained young men, a single bout of resistance exercise increases myofibrillar protein synthesis by 67% and mitochondrial protein synthesis by 69%, while a single bout of endurance exercise increases mitochondrial protein synthesis by 154% and has no effect on myofibrillar protein synthesis, demonstrating that acute exercise modality differentially regulates the synthesis rates of muscle protein fractions.
Backed by science
Randomized trialsOne low-scoring study supports this claim, so treat this as an early signal rather than settled science.
What the research says
1 study reviewedSupporting (1)
Randomized Controlled TrialHuman2008
After one workout, weightlifting boosts the muscle fibers that make you stronger by 67% and the energy parts of muscle by 69%, while running only boosts the energy parts by 154% and leaves the strength fibers unchanged. This shows that different exercises turn on different parts of your muscles.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
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When you lift weights, the force on your muscles turns on a molecular switch that tells the cell to build more contractile proteins. When you run, the energy demand in your muscles turns on the same switch but only tells the cell to build more energy-producing parts. The same molecular pathway is used in both cases, but only one type of protein gets made depending on the kind of exercise.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting study
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In untrained young men, one session of weight lifting raises the production of muscle structural proteins by 67% and energy-producing mitochondrial proteins by 69%, while one session of running raises mitochondrial protein production by 154% but does not change muscle structural protein production.
Mechanism
1 studyLifting weights and running both turn on the same cellular switch for building proteins, but lifting tells the cell to build stronger muscle fibers, while running tells it to build more energy factories. The difference comes from the type of stress the muscle feels during each activity.
When you lift weights, the force on your muscles turns on a molecular switch that tells the cell to build more contractile proteins. When you run, the energy demand in your muscles turns on the same switch but only tells the cell to build more energy-producing parts. The same molecular pathway is used in both cases, but only one type of protein gets made depending on the kind of exercise.
Resistance exercise generates high mechanical tension in muscle fibers, while endurance exercise produces sustained metabolic stress and elevated calcium levels.
Mechanical tension and metabolic stress both activate the PI3K-Akt signaling cascade, leading to phosphorylation and activation of mTORC1.
Activated mTORC1 phosphorylates p70S6K, enhancing the translation initiation machinery in the cell.
The activated translation machinery selectively increases synthesis of myofibrillar proteins (actin, myosin) during resistance exercise due to localized mechanical signaling and ribosomal targeting.
The activated translation machinery selectively increases synthesis of mitochondrial proteins (cytochrome c oxidase, ATP synthase) during endurance exercise due to metabolic signaling and coordination with nuclear-encoded mitochondrial gene expression.
Evidence from Studies
Supporting (1)
Community contributions welcome
Differential effects of resistance and endurance exercise in the fed state on signalling molecule phosphorylation and protein synthesis in human muscle
After one workout, weightlifting boosts the muscle fibers that make you stronger by 67% and the energy parts of muscle by 69%, while running only boosts the energy parts by 154% and leaves the strength fibers unchanged. This shows that different exercises turn on different parts of your muscles.
Contradicting (0)
Community contributions welcome
Score Breakdown
No multi-axis breakdown available yet. The overall Pro / Against score above is the best signal.
- No clinical evidence is available; the score reflects mechanistic plausibility only.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Systematic Review of Acute Resistance vs Endurance Exercise Effects on Myofibrillar and Mitochondrial Protein Synthesis in Untrained Young Men
Population: Untrained young men; Intervention: Single bout of resistance exercise; Comparator: Single bout of endurance exercise; Outcome: Myofibrillar and mitochondrial protein synthesis rates measured via stable isotope labeling; Duration: Single acute session
Randomized Crossover Trial Comparing Single Bout Resistance vs Endurance Exercise on Muscle Protein Synthesis in Untrained Young Men
Population: Untrained young men; Intervention: Single bout of resistance exercise; Comparator: Single bout of endurance exercise; Outcome: Myofibrillar and mitochondrial protein synthesis rates measured via muscle biopsy and stable isotope tracing; Duration: Single acute session with crossover design and washout period
Prospective Cohort Study of Acute Exercise Responses in Untrained Young Men Following Resistance or Endurance Training Sessions
Population: Untrained young men; Intervention: Group assigned to resistance or endurance exercise; Comparator: Group assigned to the alternative modality; Outcome: Myofibrillar and mitochondrial protein synthesis measured post-exercise; Duration: Single acute session with longitudinal follow-up of responses
In Vitro Study of Skeletal Muscle Cell Protein Synthesis Responses to Resistance- and Endurance-Exercise Mimetics
Population: Human skeletal muscle myotubes; Intervention: Exposure to serum from post-resistance-exercise donors; Comparator: Exposure to serum from post-endurance-exercise donors; Outcome: Myofibrillar and mitochondrial protein synthesis rates measured via radiolabeled amino acid incorporation; Duration: 24–48 hours post-exposure
Animal Model Study of Acute Resistance vs Endurance Exercise Effects on Muscle Protein Synthesis in Young Male Rodents
Population: Young male rodents; Intervention: Single bout of resistance-style loading (e.g., ladder climbing with weights); Comparator: Single bout of endurance-style treadmill running; Outcome: Myofibrillar and mitochondrial protein synthesis measured via muscle tissue analysis; Duration: Single acute session