Musculoskeletal Injury Rates in Multiday Marathon Runners Performing Ten Consecutive Marathons on a Repeat Course

Objective: To describe musculoskeletal injury rates in recreational runners completing ten marathons over ten consecutive days to help event organisers plan future injury preventative advice and strategies.
Methods: An observational study involving 27 recreational runners (age 45.1 ± 7.47 yrs, mass 74.5 ± 12.39 kg, years running 11.6 ± 9.42 yrs, average weekly mileage 41.9 ± 12.72 miles). Main outcome measures included total and percentage of musculoskeletal injuries, timing of injury occurrence during 10-day event, and daily individual marathon times.
Results: Twenty-six runners sustained 108 injuries, averaging 4 injuries per runner (90.13 per 1000hr). 89% of injuries involved the lower extremity; 24.1% foot, 18.5% hip/buttock, 16.7% ankle and 16.7% lower leg. Common injuries were blisters (15.7%), Achilles tendinitis (11.1%), medial tibial stress syndrome (MTSS) (10.2%), iliotibial band syndrome (ITBS) (9.3%) and low back pain (LBP) (9.3%). 64.3% of injuries were sustained to the left limb. Chisquared analysis revealed more injuries in days 1-3 than days 4-6 (p=0.013) and days 7-10 (p=0.001). Repeated measures ANOVA comparing Days 1-3, 4-6 and 7-10 showed a significant main effect (p=0.039). Post hoc analysis revealed Days 1-3 were significantly quicker time than days 7-10 (p=0.037, difference of 0.276 hrs).
Conclusion: Blisters, Achilles tendinitis, MTSS and ITBS are the most common lower extremity injurie in multiday marathons runners performing a repeat course over 10 consecutive days. Runners entering these events should perform appropriate injury prevention programmes. Runners should also be more reserved at the beginning of multiday events to avoid high initial injury risk. However, further investigation of injury rates and risk factors using larger sample sizes is required.