The Epidemiology, Risk Factors, and Nonsurgical Treatment of Injuries Related to Endurance Running.

ABSTRACT: Running is a popular form of exercise that is easily accessible to various populations; endurance running, defined as distances beyond 5 km, continues to grow within the sport. Endurance running-related injuries are common in the lower extremities and are primarily overuse related. A multitude of risk factors for injury exist, including extrinsic factors, such as running distance and frequency, and intrinsic factors, such as biomechanics and nutrition status. Training and rehabilitation techniques vary with a general focus on strengthening and gradual increase in activity, but evidence is mixed, and it is difficult to generalize programs across different running populations. Management of specific running groups, including youth runners, is an area in which additional research is needed. New treatments, such as orthobiologics and wearable technology, have promising potential to optimize performance and recovery and minimize injury. However, they need to be further evaluated with high-quality studies.

Longitudinal study of the morphological and T2* changes of knee cartilages of marathon runners using prototype software for automatic cartilage segmentation.

OBJECTIVE: To study the effect of long-distance running on the morphological and T2* assessment of knee cartilage. METHODS: 3D-DESS and T2* mapping was performed in 12 amateur marathon runners (age: between 21 and 37 years) without obvious morphological cartilage damage. MRI was performed three times: within 24 h before the marathon, within 12 h after the marathon, and after a period of convalescence of two months. An automatic cartilage segmentation method was used to quantitatively assessed the morphological and T2* of knee cartilage pre- and post-marathon. The cartilage thickness, volume, and T2* values of 21 sub-regions were quantitatively assessed, respectively. RESULTS: The femoral lateral central (FLC) cartilage thickness was increased when 12-h post-marathon compared with pre-marathon. The tibial medial anterior (TMA) cartilage thickness was decreased when 2 months post-marathon compared with pre-marathon. The tibial lateral posterior (TLP) cartilage volume was increased when 12-h post-marathon compared with pre-marathon. The cartilage T2* value in most sub-regions had the upward trend when 12-h post-marathon and restored trend when 2 months post-marathon, compared with pre-marathon. The femoral lateral anterior (FLA) and TMA cartilage volumes were decreased 2 months post-marathon compared with pre-marathon. CONCLUSIONS: The marathon had some effects on the thickness, volume, and T2* value of the knee cartilages. The thickness and volume of knee cartilage in most sub-regions were without significantly changes post-marathon compared with pre-marathon. T2* value of knee cartilage in most sub-regions was increased right after marathon and recovered 2 months later. The TLP and TMA subregions needed follow-up after marathon. ADVANCES IN KNOWLEDGE: The morphological and T2* changes of knee cartilage after marathon were evaluated by MRI and automatic segmentation software. This study was the first to use cartilage automatic segmentation software to evaluate the effects of marathon on the morphology and biochemical components of articular cartilage, and to predict the most vulnerable articular cartilage subregions, for the convenience of future exercise adjustment and the avoidance of sports cartilage injury.

The Impact of the COVID-19 Pandemic on Endurance and Ultra-Endurance Running.

Background and objectives: The COVID-19 outbreak has become a major health and economic crisis. The World Health Organization declared it a pandemic in March 2020, and many sporting events were canceled. Materials and Methods: We examined the effects of the COVID-19 pandemic on endurance and ultra-endurance running (UER) and analyzed finishes and events during the COVID-19 pandemic (observation period March 2020-October 2020) to the same time period pre-COVID-19 outbreak (March 2019-October 2019). Results: Endurance finishes decreased during the pandemic (459,029 to 42,656 (male: 277,493 to 25,582; female 181,536 to 17,074; all p < 0.001). Similarly, the numbers of endurance events decreased (213 vs. 61 events; p < 0.001). Average marathon finishing times decreased during the pandemic in men (5:18:03 ± 0:16:34 vs. 4:43:08 ± 0:25:08 h:min:s (p = 0.006)) and women (5:39:32 ± 0:19:29 vs. 5:14:29 ± 0:26:36 h:min:s (p = 0.02)). In UER, finishes decreased significantly (580,289 to 110,055; p < 0.001) as did events (5839 to 1791; p < 0.001). Popular event locations in United States, France, UK, and Germany decreased significantly (p < 0.05). All distance and time-limited UER events saw significant decreases (p < 0.05). Conclusions: The COVID-19 pandemic has had a significant effect on endurance and UER, and it is unlikely that running activities return to pre-pandemic levels any time soon. Mitigation strategies and safety protocols should be established.

Number of finishers and performance of age group women and men in long-distance running: comparison among 10km, half-marathon and marathon races in Oslo.

The aim of the present study was to examine the number of finishers and performance trends in 10 km, half-marathon and marathon races in Oslo. Data (total 115,725 finishers; women, n = 50,595; men, n = 65,130) from 10 km, half-marathon and marathon races in Oslo from 2008 to 2018 were analysed considering number, sex, age and running speed of finishers. The total men-to-women ratio was the smallest in the 10 km race (0.60) and the largest in the marathon (3.86) (p < 0.01, φ = 0.28). In both women and men, the slowest running speed was shown in the older age groups (p < 0.01). Based on the findings of the present study, it was concluded that relatively more women finished a 10 km and less a half-marathon and a marathon. Our results indicated that the sex difference in performance was attenuated in the longer race distances and older age groups.

Training for a (half-)marathon: Training volume and longest endurance run related to performance and running injuries.

OBJECTIVE: Examine the associations of training volume and longest endurance run with (half-)marathon performance and running-related injuries (RRIs) in recreational runners. MATERIALS AND METHODS: During the preparation for and directly after the running event, 556 participants of a half marathon and 441 participants of a marathon completed three questionnaires on RRIs, average weekly training volume and the longest endurance run. With finish time, decline in pace during the running event and RRIs as dependent variables, linear and logistic regression analyses were performed to test the associations with weekly training volume and the longest endurance run. RESULTS: In half-marathon runners, a high training volume (>32 km/wk) (ß -4.19, 95% CI: -6.52;-1.85) and a long endurance run (>21 km) (ß -3.87, 95% CI: -6.31;--1.44) were associated with a faster finish time, while a high training volume (ß -1.81, 95% CI: -3.49;-0.12) and a long endurance run (ß -1.89, 95% CI: -3.65;-0.12) were also related to less decline in pace. In marathon runners, a low training volume (<40 km/wk) was related to a slower finish time (ß 6.33, 95% CI: 0.18;12.48) and a high training volume (>65 km/wk) to a faster finish time (ß -14.09, 95% CI: -22.47;-5.72), while a longest endurance run of <25 km was associated with a slower finish time (ß 13.44, 95% CI: 5.34;21.55). No associations between training characteristics and RRIs were identified. CONCLUSIONS: Preparation for a (half-)marathon with a relatively high training volume and long endurance runs associates with a faster finish time, but does not seem related to an increased injury risk.

Calculation of Critical Speed from Raw Training Data in Recreational Marathon Runners.

INTRODUCTION: Critical speed (CS) represents the highest intensity at which a physiological steady state may be reached. The aim of this study was to evaluate whether estimations of CS obtained from raw training data can predict performance and pacing in marathons. METHODS: We investigated running activities logged into an online fitness platform by >25,000 recreational athletes before big-city marathons. Each activity contained time, distance, and elevation every 100 m. We computed grade-adjusted pacing and the fastest pace recorded for a set of target distances (400, 800, 1000, 1500, 3000, and 5000 m). CS was determined as the slope of the distance-time relationship using all combinations of, at least, three target distances. RESULTS: The relationship between distance and time was linear, irrespective of the target distances used (pooled mean ± SD: R = 0.9999 ± 0.0001). The estimated values of CS from all models were not different (3.74 ± 0.08 m·s), and all models correlated with marathon performance (R = 0.672 ± 0.036, error = 8.01% ± 0.51%). CS from the model including 400, 800, and 5000 m best predicted performance (R = 0.695, error = 7.67%) and was used in further analysis. Runners completed the marathon at 84.8% ± 13.6% CS, with faster runners competing at speeds closer to CS (93.0% CS for 150 min marathon times vs 78.9% CS for 360 min marathon times). Runners who completed the first half of the marathon at >94% of their CS, and particularly faster than CS, were more likely to slowdown by more than 25% in the second half of race. CONCLUSION: This study suggests that estimations of CS from raw training data can successfully predict marathon performance and provide useful pacing information.

Marathon pacing ability: Training characteristics and previous experience.

Abstract Even pacing within the marathon has been associated with faster marathon performance times, however, little literature has investigated the association between pacing ability during a marathon and a recreational marathoner's training characteristics and previous experiences. N = 139 participants completed an online questionnaire concerning training history in relation to a 2017 marathon and previous long-distance running experiences. Online databases were used to collect split times of the participants after successfully completing a 2017 marathon, identifying the percentage slowdown in pace between the first half and second half of the marathon, used for correlational analyses. The strongest correlates for pacing ability were marathon finishing time and previous distance race personal best finishing times (i.e. marathon, half-marathon, 10 and 5 km). There were many weaker, however significant correlates for training history characteristics and previous long-distance running experience. The current findings demonstrate that greater accrued long-distance running experiences and higher weekly training volumes are strongly associated with smaller declines in pace during the second half of the marathon in comparison to the first half and less variability in pace during the marathon.

Deliberate practice in training differentiates the best Kenyan and Spanish long-distance runners.

The aim of this novel research was to compare the amount of systematic training and the different training activities undertaken by elite-standard long-distance runners during their first seven years of systematic training. Participants were divided into three performance groups: world-class Kenyans (N = 19), European-standard Spanish athletes (N = 18), and Spanish national-standard athletes (N = 18). Performance and training data were obtained for two-year periods using retrospective recall (including training diaries) from the time the athletes began systematic training, until the seventh year after. These activities included high-intensity training sessions considered deliberate practice (DP) and easy runs. There was no evidence that starting systematic training at a younger age was advantageous, and easy runs (a non-DP activity) were the most used by participants as a proportion of overall running distance. As part of an overall higher accumulation of distance run (P < 0.001, d ≥ 1.35), the Kenyans completed more tempo runs and short-interval training than the other groups (P < 0.001, d ≥ 1.38), but did not complete more long intervals or races. There were few differences between the European- and national-standard athletes except for easy runs, which highlights the value of these easy runs but also the need for higher-intensity training to compete with world-class performers. When planning for training overload and progression, long-distance running coaches should consider increasing the volume of tempo runs and short intervals, in addition to easier runs that develop cardiovascular conditioning.