Table 2

Summary of included article characteristics

Types of athletesSample characteristics
National level*17 (27.8%)Mean sample size (n)444
Collegiate/university15 (24.6%)Median sample size (n)217
Professional15 (24.6%)Mean age of sample (years)24.5
Mixed levels7 (11.5%)Median age of sample (years)23.9
Professional youth4 (6.6%)Mean retirement length (years)5.9
Olympic3 (4.9%)Aggregate sample size27 515
Types of s ports Aggregate male athletes16 547 (60%)
Multiple29 (48%)Aggregate female athletes7964 (28.9%)
Soccer13 (21%) Study d esign
Rugby5 (8%)Cross-sectional36 (59%)
Basketball3 (5%)Cohort17 (28%)
Track and field3 (5%)Longitudinal2 (3%)
Gaelic sports (eg, hurling)2 (3%)Experimental2 (3%)
American football1 (2%)Quasi-experimental2 (3%)
Baseball1 (2%)Randomised clinical trial1 (2%)
Golf1 (2%)Mixed design1 (2%)
Ice hockey1 (2%)
Swimming1 (2%)
  • *One sample included national rookies.