Table 2.

Continued From Previous Page

Authors	Study Design	Follow-Up	Sample Size (% Females)	Type of Runners	Mean Age ± SD, y	Age Range	Running Program	Reported RRI Incidence	Association Between RRIs and Training Parameters	Recent Changes in Training Parameters
Ramskov et al30	RCT	24 wk	n = 839; 447 analyzed (62.1%)	Recreational	39.1 ± 10.2		16-wk Running program based on progression of either running intensity (S-I) or volume (S-V); 3 runs/wk, 4-wk periodization cycle repeated ×6. Wk 1 in every cycle ↑ volume by 23% Wk 2–3: Adaptation, 0% progression Wk 4: Volume ↓ by 10% Progression/regression of running in S-I = % change in km/wk at intensity ≤88% maximal oxygen consumption	17.9% (80/447) S-I group: 16.3% (36/221); 8/36 intensity related, 5/36 volume-related S-V group: 19.5% (44/226); 11/44 intensity related, 9/44 volume related No difference in risk of intensity or volume RRI between runners in S-I and S-V groups during 16-wk follow-up		Recent changes: No differences in overall RRI incidence between progression of distance or intensity or type of injuries sustained by each group (distance: P > .14, intensity: P > .32)
Taunton et al31	Prospective	13 wk	n = 844 (75.2%)	Recreational		Age by category: <30 y (16.8%), 31–49 y (59.8%), 50–55 y (13.2%), >56 y (8.8%)	13-wk Program to complete 10-km race	29.5% (249/844)	Running frequency: ↓ Running (only 1 d/wk) associated with ↑ RRI risk in overall cohort and female runners (OR = 3.6, 95% CI = 1.1, 12.3) but not in male runners
van der Worp et al35	Prospective	12 wk	n = 417 (100%)	Recreational	38.7 ± 11.5		Self-selected running program	22.3% (93/417)	Running distance: Distance/wk >30 km associated with ↑RRI risk (HR = 3.28, 95% CI = 1.23, 8.75) <10 km: 28.3% (41/145) 10–20 km: 25.0% (30/120) 21–30 km: 34.8% (16/46) >30 km: 46.2% (6/13)
van Middelkoop et al32	Prospective	4 wk	n = 694 (0%)	Recreational	44 ± 9.6		Self-selected running program during 4 weeks leading up to marathon	28.1% (195/694)	Running distance: Volume/wk <40 km protected against calf injuries (OR = 0.36, 95% CI = 0.17, 0.78) Running intensity: Consistent interval training protected against knee injuries (OR = 0.49, 95% CI = 0.26, 0.93)
van Poppel et al33	Prospective	12 mo	n = 3768 (39.2%)	Recreational	42.8 ± 11.2		Usual running routine	21.5% of runners (811/3,768) reported RRIs: 17.5% of 5-km runners (67/250) reported RRIs; 18.7% of 10-km or 15-km runners (257/981) reported RRIs; 23.1% of half marathon runners (214/708) reported RRIs; 25.2% of marathon runners (266/762) reported RRIs	Running distance: A greater weekly distance was associated with ↓ risk of RRI (OR = 0.99, 95% CI = 0.98, 1.0) Running frequency: No association with risk of RRI (OR =1.3, 95% CI = 0.99, 1.7) Running intensity: No association with risk of RRI
Walter et al42	Prospective	12 mo	n = 1288 (23.5%)	Recreational, Competitive		Age by category: 14–19 y = 11.3%; 20–29 y = 21.2%; 30–39 y = 39.3%; 40–49 y = 21.0%; >50 y = 7.1%	Usual running routine	48.1% of runners (620/1288) reported RRIs	Running distance: A greater weekly distance (over 64 km) was associated with ↑ risk of RRI (adjusted relative risk = 2.88). Relative risk in males = 2.22, 95% CI = 1.30, 3.68. Relative risk in females = 3.42, 95% CI = 1.42, 7.85. Running frequency: Running 7 d/wk was associated with significantly ↑ risk of RRI compared with 0–2 d/wk in both males (relative risk = 5.92, 95% CI = 2.49, 12.75) and females (relative risk = 5.50, 95% CI = 1.44, 17.39). Running intensity: No association with risk of RRI
Wen et al49	Prospective	32 wk	n = 108 (52.8%)	Novice, Recreational	43.2 ± 9.8		32-wk Program leading up to marathon; organized sessions weekly; own program during week	45.4% (49/108); 1.22 injuries/1609.3 km (95% CI = 0.97, 1.48)	Running distance: ↑ Distance associated with ↓ risk of knee RRI (relative risk = 0.901, 95% CI = 0.820, 0.991). Running duration: ↑ Training h/wk associated with ↓ overall RRIs (relative risk = 0.575, 95% CI = 0.451, 0.731), ↓ knee injuries (relative risk = 0.486, 95% CI = 0.297, 0.795), ↓ foot injuries (relative risk = 0.206, 95% CI = 0.096, 0.444)
Winter et al43	Prospective	12 mo	n = 76 (40.8%)	Recreational, Competitive	Injured = 40.7 ± 12.5; uninjured = 44.8 ± 12.5		Self-selected running program	51.3% (39/76)	Running distance: ↑ Average distance/wk in injured vs uninjured male runners (r = 0.32, P = .046); no difference in female runners	Recent changes: Injured male (n = 20; 91%) and female (n = 10; 59%) runners ↑ distance/wk by >10% between consecutive wk at least 1x in 4 wk before injury. Of 18 injured male runners who ↑ running distance by >10% 1x, 11 (61%) ↑ by >30%, and 5 (28%) ↑ by >50%. Of 9 injured female runners who ↑ running distance by >10% 1x, 5 (56%) ↑ by >30% and 3 (33%) ↑ by >50%.

Abbreviations: GTG, graded training group; HR, hazard ratio; ITV, increased training volume; ITI, increased tempo pace and interval runs; IQR, interquartile range; OR, odds ratio; RCT, randomized clinical trial; RD, risk difference; RRI, running-related injury; STG, standard training group.