Shoulder Rotational Strength Profiles of Danish National Level Badminton Players.
Martin B Stausholm, Martin Baun, Jan M Bjordal and 4 others
PMID 33842046WHAT IT FOUND
Injury-free adolescent badminton players had stronger shoulder external rotation than adults on both sides.
Adults showed an imbalance with dominant-side internal rotation strength not matched by external rotation. This suggests external rotator weakness may develop with age in overhead athletes.
Key findings
01Adolescent players had stronger shoulder external rotation than adult players on both the dominant and non-dominant sides.
02Adult players had a lower ratio of external to internal rotation strength on the dominant shoulder compared to adolescents, indicating a relative weakness of the external rotators.
03Adolescent females and males had 25% and 13% stronger dominant shoulder external rotation than their adult counterparts, respectively.
STILL TO COME
How it was doneWhat they foundWhat it means for PTs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study is cross-sectional, so it cannot prove that aging or playing badminton caused the strength changes; it only shows a difference at one point in time. The sample size was relatively small, particularly for the female groups, which may affect the statistical power of the findings. Strength was measured isometrically, whereas badminton involves dynamic and eccentric movements, which might not be fully captured by this method. The moment arm measurement likely overestimated torque values, and the number of hours played was not recorded, so the impact of training volume versus age could not be separated.
Declared interests
The authors have no conflicts of interest to disclose, and no outside funding was received for this work.
The easy way to misread this
Do not interpret the lower external rotation strength in adults as proof that badminton caused it. The study design cannot separate the effects of aging from the effects of long-term sport participation, and no injury outcomes were measured.