The Claim

In recreationally active adults, an 8-week resistance training program consisting of 5 sets of 10–12 repetitions performed 3 days per week is associated with an approximately 10% increase in maximal isometric strength of the pectoralis major muscle, with no significant change in shoulder range of motion compared to a control group.

Source: Influence of 8-weeks of supervised static stretching or resistance training of pectoral major muscles on maximal strength, muscle thickness and range of motion

What the research says

Supports is higher

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

Supports
47score
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.

Quantitative
1 study reviewed
In plain English

If you're someone who exercises regularly, doing chest workouts 3 times a week for 8 weeks might make your chest muscles about 10% stronger, but it won’t change how far you can move your shoulders.

See the scientific wording

In recreationally active adults, 8 weeks of resistance training (5 sets of 10–12 repetitions, 3 days per week) is associated with approximately 10% increase in maximal isometric strength of the pectoralis major, with no significant change in shoulder range of motion compared to control.

What the research says

1 study
  1. Study: Influence of 8-weeks of supervised static stretching or resistance training of pectoral major muscles on maximal strength, muscle thickness and range of motion

    The study found that lifting weights 3 times a week for 8 weeks made chest muscles stronger, just like the claim says, and didn’t make shoulders more flexible, which also matches.

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.