Can the workload-injury relationship be moderated by improved strength, speed and repeated-sprint qualities?

Key points

1. 01Moderate weekly loads (about 1400 to 1900 AU) were protective against injury versus low loads, in both pre-season and in-season.
2. 02Slower athletes over 5, 10 and 20 m had roughly three times the injury odds of faster athletes.
3. 03Stronger athletes tolerated bigger week-to-week load spikes with lower injury odds than weaker athletes.
4. 04Athletes with better repeated-sprint times were at lower injury risk when weekly load was high (1750 AU or more).
5. 05An acute-to-chronic workload ratio of about 0.90 to 1.30 was protective and the ratio explained about 60% of injury variance.

How it was conducted

Design

Observational cohort study over two seasons

Participants

40 male amateur hurling players (age 26.2 plus or minus 4.4 yr), median 5 years experience

Exposure tracked

Workload as session-RPE times duration, weekly load and acute-to-chronic workload ratio

Physical qualities

3-rep-max trap-bar deadlift, 5/10/20-m sprint times, and 6 x 35-m repeated-sprint ability

Outcome

Time-loss injuries preventing full participation for more than 24 h

Analysis

Chi-squared and second-order polynomial regression, quartiles, odds ratios vs a reference group; statistical power 83%

What they found

• 93 time-loss injuries occurred across two seasons; thigh 35%, ankle 17%, pelvis/groin 14%, knee 11%.
• Moderate weekly loads (1400 to 1900 AU) were protective pre-season (OR 0.44, 95% CI 0.18 to 0.66) and in-season (OR 0.59, 95% CI 0.37 to 0.82) versus 1200 AU or less.
• Large weekly load changes of 1000 AU or more raised injury risk pre-season (OR 5.58, 95% CI 3.19 to 7.32) and in-season (OR 4.98, 95% CI 2.33 to 5.36).
• Slower athletes had higher injury odds at 5-m (OR 3.11, 95% CI 2.33 to 3.87), 10-m (OR 3.45, 95% CI 2.11 to 4.13) and 20-m (OR 3.12, 95% CI 2.11 to 4.13).
• Athletes with better repeated-sprint total time at weekly load 1750 AU or more had reduced risk versus those with poor times (OR 5.55, 95% CI 3.98 to 7.94).
• Stronger athletes tolerated load and spikes better (OR range 1.33 to 5.10); at ACWR above 1.25 the strength quartile OR was 5.10 (95% CI 3.98 to 6.10, p = 0.003).
• The acute-to-chronic workload ratio explained about 60% of injury likelihood (R2 = 0.60, 95% CI 0.23 to 0.87).

Limitations

• Small single cohort of 40 amateur male hurling players, so results may not generalise to other sports, women or elite players.
• Observational design shows association, not cause; physical qualities and injury risk could be confounded by other factors.
• Workload was measured by self-reported session-RPE, which is subjective.
• Some odds-ratio confidence intervals are wide, reflecting limited sample size.

Why it matters

For patients

Building lower-body strength, speed and repeated-sprint fitness may help an athlete handle hard training with less injury, but this single small study cannot promise that.

For clinicians

In team-sport athletes, screening strength, speed and repeated-sprint ability may help flag who tolerates higher loads, alongside sensible weekly load progression.

For readers

This is early, association-level evidence from one small amateur cohort, so treat the protective findings as a reasonable hypothesis rather than established fact.