The Claim

Low-intensity dynamic plantar flexion exercise performed at 25% of one-repetition maximum with the knee fully extended selectively increases post-exercise T2 MRI signals in the superficial calf muscles (medial and lateral gastrocnemius and peroneus) without significantly altering signals in the deep soleus or anterior tibialis, indicating preferential recruitment of superficial calf musculature under these biomechanical conditions.

Source: Comparison of MRI with EMG to study muscle activity associated with dynamic plantar flexion.

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
27score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

How it works
1 study reviewed
In plain English

When you do light calf raises with your knees straight, the exercise mainly works the outer and back parts of your lower leg muscles while leaving the deeper calf and shin muscles mostly untouched. This shows that keeping your knees straight during light resistance training specifically targets the more superficial muscles in your calves.

See the scientific wording

Dynamic plantar flexion at 25% of one-repetition maximum produces significant post-exercise T2 signal increases in the medial and lateral gastrocnemius and peroneus muscles when the knee is fully extended, but does not significantly alter T2 signals in the soleus or anterior tibialis under the same conditions. This selective activation pattern demonstrates that low-intensity resistance exercise preferentially recruits superficial calf muscles when the knee is straight.

What the research says

1 study

  1. Study: Comparison of MRI with EMG to study muscle activity associated with dynamic plantar flexion.

    When you do light calf raises with your knees straight, the MRI shows that the main calf muscles and side leg muscles get more active, while the deeper calf muscle and shin muscle stay relatively quiet. This proves that straight-legged, low-intensity calf exercises specifically target the outer calf muscles.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.