Are there really many runners out there? Is the proportion of runners increasing over time? A population-based 12-year repeated cross-sectional study with 625,460 Brazilians.

OBJECTIVES: To investigate the proportion of individuals who practice running, its temporal trend, and to describe the runners' characteristics. DESIGN: Population-based repeated cross-sectional study. METHODS: The data from the Protective and Risk Factors for Chronic Diseases by Telephone Survey (Vigitel) from Brazil were used. Telephone interviews were conducted with adults from the Brazilian capitals (27 cities) between 2006-2017. The interviewer read the questions and recorded the participants' responses immediately in a questionnaire. Data analyses were conducted using a Bayesian approach. RESULTS: The Vigitel database consisted of 625,460 Brazilian participants composed of 295,681 exercisers and within them 15,529 runners. The mean yearly proportion of runners was about 2.45% (95% Bayesian credible interval [CrI] 1.93 to 3.11) and 5.32% (95%CrI 4.29 to 6.54) in the entire study population and within exercisers, respectively. The absolute increase in the proportion of runners per year over the 12-year period was 0.13% and 0.17% in the entire study population and within exercisers, respectively. Runners were more likely to be younger, men, within normal body mass index, highly educated, moderate alcohol drinkers, non-smokers, less exposed to TV, living near physical activity/sports facilities and less exposed to health conditions such as arterial hypertension, diabetes and dyslipidaemia. CONCLUSION: There was a 95% probability that the yearly proportion of runners lies between 1.93% and 3.11% in the population of the 27 Brazilian capitals, and between 4.29% and 6.54% within exercisers. There has been an increase in the proportion of runners over time. Runners were associated with healthier characteristics compared to non-runners and non-exercisers.

Half marathon induces changes in central control and peripheral properties of individual motor units in master athletes.

Acute changes in central control and peripheral properties of motor units following a half-marathon has never been examined in master athletes. Therefore, the main purpose of this study was to estimate the firing properties and twitch characteristics of motor units after a 21-km race in a group of ten trained older adults. High-density surface EMG decomposition was used to identify motor unit activity during a submaximal contraction of the tibialis anterior muscle before and after the half marathon. The area of the estimated motor unit twitch profile was found smaller after the race (P = 0.039). This reduction in contractile efficiency was compensated by a significant increase in the initial and average discharge rate of the identified motor units (P < 0.001). By estimating the amount of shared and independent synaptic input to tibialis anterior motor neurons, we demonstrated that adaptations in the discharge properties of master athletes' motor units are the likely consequence of an increased net excitatory synaptic drive to the motor neuron pool. These findings suggest a potential role of long-distance running in ameliorating declines in muscle function of older adults by enhancing the neural drive to muscle.

The "New York City Marathon": participation and performance trends of 1.2M runners during half-century.

The aim of the present study was to examine trends in participation, performance, age and nationality during a ~ 50-years period in the largest dataset ever studied in the "New York City Marathon". We analysed 1,174,331 finishers (women, n= 349,145, age 39.7 ± 8.7 years; men, n= 825,186, 41.7 ± 9.2 years). The overall participation increased across calendar years for all nationalities, and this increase was more pronounced in women, which resulted in a decreasing men-to-women ratio. Men were faster and older than women. Ethiopians and Kenyans were the fastest and youngest in women and men, respectively. Japanese were the slowest and Germans were the oldest in both sexes. Race time increased across years. Coaches and fitness trainers should be aware of these trends and should emphasize the development of training programs for older and slower runners.

Is there any difference between "amateur" and "recreational" runners? A latent class analysis

Abstract Aims: to identify and describe the clustering of characteristics related to running amongst Brazilian runners using latent class analysis and to verify if there is a profile associated with better performance. Material and Methods: a sample of 1149 Brazilian runners answered an online questionnaire, that provided information about biological (sex, age, height, weight), training (running pace, frequency and volume/week, motivation), and socioeconomic factors, as well as a multidimensional questionnaire of fear of failure. Latent Class Analysis was used to identify subgroups of Brazilian runners, based on BMI, training volume and frequency/week, motivation, socioeconomic factors, and the fear of failure. Further, a χ2 test was computed to verify statistical differences in the frequency of the descriptive variables between classes. Finally, binary logistic regression analysis estimated factors associated with running performance, with running pace as the dependent variable. Results: It was possible to identify two different classes among Brazilian runners, which were called "amateur runners" and "recreational runners". Variables that highlighted classes' differences were: volume and frequency training/week, motivation for the practice, and BMI. Regarding the running performance, logistic regression analysis showed that men (OR=5.39; 95%CI=4.00-7.25), young runners (OR=0.38; 95%CI=0.28-0.51), and "amateur runners" (OR=4.19; 95%CI=2.95-5.94) were more prone to have higher performance. Conclusion: Two distinct classes were found among Brazilian runners that were linked to their performance, highlighting that even among non-professional runners, differences can be observed regarding their classification. Hence, future studies should consider using these classes to properly stratify or identify non-professional runners.

The Temporal and Spatial Evolution of Marathons in China from 2010 to 2018.

The purpose of this study is to explore the spatial distribution pattern and influencing factors of the Chinese marathon. Geographic Information System (GIS) related spatial analysis tools were used to calculate the following-averaged nearest neighbor index, nuclear density analysis and hot spot analysis among others. The spatial distribution evolution characteristics and the influencing factors of eighteen Chinese marathon events in 2010, 129 in 2015 and 342 in 2018 were analyzed. The results show that (a) in 2010 the nearest neighbor ratio was 1.164714, Moran's I was -0.010165 (type: Random), in 2015 it was 0.502146, Moran's I was 0.066267 (type: Clustered) and in 2018 it was 0.531149 and Moran's I was 0.083485 (type: Clustered); (b) in 2010 there was a 333.6 km search radius; the core circle of the Yangtze River Delta was adopted. In 2015 and 2018, a search radius of 556 km was adopted, which was respectively obtained from the core circle of the Yangtze River Delta, the core circle of Beijing-Tianjin-Hebei and the core circle of East China; (c) according to the Z-value data, East China and North China in 2015 passed 95% confidence in five provinces and municipal hot spots, passed 90% confidence in three hot spots and passed 95% confidence in Chongqing Cold Point. In 2018, East China, North China, Central Region and eight other provinces and cities' hot spots passed 95% confidence, four hot spots passed 90% confidence, the Tibet Autonomous Region cold spot passed 90% confidence. Conclusion: The overall distribution of marathon events is greater in the eastern region than the western region, greater in the southern region than the northern region and greater in coastal regions than the inland regions; the nuclear density distribution has spread from the Yangtze River Delta mononuclear circle in 2010 to the core circle of the entire East China region. Moreover, it spread to North China, Central China and South China; the distribution of hot spots spread from Shanghai, Jiangsu and Zhejiang to the entire North China and East China regions. During the past thirty-eight years of development of the Chinese marathon, it has been divided into three stages due to different political, economic and social environments.

Current Trends in Ultramarathon Running.

Exercise is universally recognized for its health benefits and distance running has long been a popular form of exercise and sport. Ultramarathons, defined as races longer than a marathon, have become increasingly popular in recent years. The diverse ultramarathon distances and courses provide additional challenges in race performance and medical coverage for these events. As the sport grows in popularity, more literature has become available regarding ultramarathon-specific illnesses and injuries, nutrition guidelines, psychology, physiologic changes, and equipment. This review focuses on recent findings and trends in ultramarathon running.

Changes in Player Activity Profiles After the 2015 FIH Rule Changes in Elite Women's Hockey.

McMahon, GE and Kennedy, RA. Changes in player activity profiles after the 2015 FIH rule changes in elite women's hockey. J Strength Cond Res 33(11): 3114-3122, 2019-The aim of this study was to compare the player activity profiles of elite international women's hockey players before (2014) and after (2015) the 2015 the International Hockey Federation (FIH) match rule changes at team and positional levels. The match activity profiles (n = 400) of 19 female hockey players (age 23 ± 4 years, mass 63.6 ± 5.5 kg, VO2max 57 ± 6 ml·kg·min in 2014, 58 ± 6 ml·kg·min in 2015) were recorded during competitive international matches in 2014 (match n = 12) and 2015 (match n = 13) using 10-Hz global positioning system units. The practical utility of an effect was only classified as substantial when there was a >75% likelihood that the ±90% confidence interval of the effect size (ES) was equal to or greater than the small (ES ± 0.2) reference value. Mean match time decreased by over 2 minutes from 71.72 ± 1.38 to 69.40 ± 4.72 minutes. There were increases at the team level in relative substitutions (SUB), relative distance (RD), high-speed running (HSR: 3.08-5.27 m·s), and surges (S), with a fall in low-speed running (LSR: 0-3.05 m·s) between 2014 and 2015. There were no changes in the between-position differences observed from 2014 to 2015. Within positions, there were relative increases in RD for all positions, HSR and S for midfield, and in SUB and S in forwards. The 2015 FIH rule changes seem to have increased the general intensity of international women's hockey. However, the different facets of physical performance did not change uniformly across team positions. Therefore, specific modifications to conditioning practices for each position may be warranted to more accurately reflect match demands.

Improved Performance in Master Runners Competing in the European Championships Between 1978 and 2014.

Schneider, AL, Nikolaidis, PT, and Knechtle, B. Improved performance in master runners competing in the European championships between 1978 and 2014. J Strength Cond Res 33(9): 2559-2569, 2019-The performance trends in elite runners have been well investigated, but we have no knowledge about performance trends and the difference between the sexes in elderly runners competing at a high level in varying distances. The purpose of this study was to investigate the performance of these age groups. Data from 17 European Championships held between 1978 and 2014 were analyzed for various race distances (i.e., 100, 200, 400, 800, 1,500, 5,000, 10,000 m, and marathon). Running speed for the top 8 female and male finalists for each age group (35-99 years, split into 5-year gaps) and each race distance were included. A 2-way analysis of variance compared the effects of sex, race distance, age group and calendar year on speed. Subsequent comparisons between race distances, age groups, or calendar years were performed using a post hoc Bonferroni's test. Our analysis shows that men were faster than women in all distances, and the difference between the sexes was greater in the shorter distances. Speed was higher for shorter distances than for longer distances. Younger participants were faster than older ones, and the effect of age group was the largest for the 200 m. There was a minor effect of calendar year on speed in the 100, 20, 1,500, 10,000 m and marathon, and a minor calendar year × sex interaction on running speed was shown for the 200 m. For athletes and coaches, the current study demonstrates that both male and female athletes improved their running performance over time and that the sex gap may have reached its limit.

Maximal Sprint Speed and the Anaerobic Speed Reserve Domain: The Untapped Tools that Differentiate the World's Best Male 800 m Runners.

Recent evidence indicates that the modern-day men's 800 m runner requires a speed capability beyond that of previous eras. In addition, the appreciation of different athlete subgroups (400-800, 800, 800-1500 m) implies a complex interplay between the mechanical (aerial or terrestrial) and physiological characteristics that enable success in any individual runner. Historically, coach education for middle-distance running often emphasises aerobic metabolic conditioning, while it relatively lacks consideration for an important neuromuscular and mechanical component. Consequently, many 800 m runners today may lack the mechanical competence needed to achieve the relaxed race pace speed required for success, resulting in limited ability to cope with surges, run faster first laps or close fast. Mechanical competence may refer to the skilled coordination of neuromuscular/mechanical (stride length/frequency/impulse) and metabolic components needed to sustain middle-distance race pace and adjust to surges efficiently. The anaerobic speed reserve (ASR) construct (difference between an athlete's velocity at maximal oxygen uptake [v[Formula: see text]O2max]-the first speed at which maximal oxygen uptake [[Formula: see text]O2max] is attained) and their maximal sprint speed (MSS) offers a framework to assess a runner's speed range relative to modern-day race demands. While the smooth and relaxed technique observed in middle-distance runners is often considered causal to running economy measured during submaximal running, little empirical evidence supports such an assumption. Thus, a multidisciplinary approach is needed to examine the underpinning factors enabling elite 800 m running race pace efficiency. Here, we argue for the importance of utilising the ASR and MSS measurement to ensure middle-distance runners have the skills to compete in the race-defining surges of modern-day 800 m running.

Upward running is more beneficial than level surface or downslope running in reverting tibia bone degeneration in ovariectomized rats.

OBJECTIVE: We investigated the effects of upslope, level surface, and downslope running on indices of tibia and femur bone recovery in ovariectomized (OVX) rats. METHODS: Rats were randomly divided into five groups: one sham-operated (SHAM) group and four OVX groups. One OVX group was a non-running control (OVX-Cont) and the others performed upslope running (OVX-Up), level surface running (OVX-Level), or downslope running (OVX-Down) on a treadmill after ovariectomy. The metaphysis region of the proximal tibia, distal femur, and proximal femur were scanned by micro-computed tomography and various geometric and microarchitectural parameters as well as bone mineral density measured using bone analysis software. RESULTS: Tibial bone geometric parameters, BV/TV and trabecular thickness, were significantly improved in OVX-Up and OVX-Level groups compared to that in OVX-Cont and OVX-Down groups, and improved to a greater degree in OVX-Up group than in OVX-Level group. CONCLUSIONS: Therefore, running slope substantially influences the beneficial effects of treadmill running on OVX-induced bone degeneration, with upward running being more effective than level surface running or downslope running, likely due to the greater bone loads associated with upslope running. The benefits of upslope treadmill running were particularly observed in the proximal tibia.

Performance trends in age-group runners from 100 m to marathon-The World Championships from 1975 to 2015.

This study examined changes in performance in age-group track runners across years from 1975 to 2015 for 100, 200, 400, 800, 1500, 5000, 10 000 m, and marathon and the corresponding sex differences. Athletes were ranked in 5-year age-group intervals from 35-39 to 95-99 years. For all races and all years, the eight female and male finalists for each age-group were included. Men were faster than women and this observation was more pronounced in the shorter distances. The younger age-groups were faster than the older age-groups and age exerted the largest effect on speed in 800 m and the smallest in marathon. There was a small variation of speed by calendar years. The competition density varied by sex and race distance. Half of participants were from USA, Germany, Australia, and Great Britain, but the participants' nationality varied by sex and race distance. In summary, the variation of competitiveness by sex in short race distances might be important for athletes and coaches. Considering the event's competitiveness and that athletes are participating in both 100 and 200 m or in 200 and 400 m, master women should be oriented to 200 m and master men should be oriented to 100 and 400 m.

Strenuous running exacerbates knee cartilage erosion induced by low amount of mono-iodoacetate in rats.

BACKGROUND: It is still debated whether strenuous running in the inflammatory phase produces beneficial or harmful effect in rat knees. We examined (1) the dropout rate of rats during a 30-km running protocol, (2) influences of strenuous running and/or low amounts of mono-iodoacetate injection on cartilage, and (3) the effect of strenuous running on synovitis. METHODS: Rats were forced to run 30 km over 6 weeks and the dropout rate was examined. One week after 0.1 mg mono-iodoacetate was injected into the right knee, rats were forced to run either 15 km or not run at all over 3 weeks, after which knee cartilage was evaluated. Synovium at the infrapatellar fat pad was also examined histologically. RESULTS: Even though all 12 rats run up to 15 km, only 6 rats completed 30 km of running. Macroscopically, 0.1 mg mono-iodoacetate induced erosion at the tibial cartilage irrespective of 15 km of running. Histologically, 0.1 mg mono-iodoacetate induced loss of cartilage matrix in the tibial cartilage, and an additional 15 km of strenuous running significantly exacerbated the loss. Synovitis caused by mono-iodoacetate improved after running. CONCLUSIONS: Only 50% of rats completed 30 km of running because of foot problems. Strenuous running further exacerbated tibial cartilage erosion but did not influence synovitis induced by mono-iodoacetate.

Improved Race Times in Marathoners Older than 75 Years in the Last 25 Years in the World's Largest Marathons.

Performance trends of elite marathoners are well investigated. However, performance of elderly marathoners (> 75 years) competing in the world's largest city marathons is not well-known. We examined marathon race data of 1,691 marathon finishes (i.e. 218 women and 1,473 men) competing between 1990 and 2014 in 5-year age groups 75-79, 80-84, 85-89, and 95-99 years in four races (Berlin, New York, Chicago and Boston) of the 'World Marathon Majors'. The number of female (r² = 0.50, P < 0.0001) and male (r² = 0.88, P < 0.0001) finishers increased significantly across years. The number of women (r² = 0.36, P = 0.0019) and men (r² = 0.88, P < 0.0001) in age group 75-79 years increased. In age group 80-84 years, the number of women (r² = 0.36, P = 0.0111) and men (r² = 0.54, P < 0.0001) also increased. In age groups 85-89 to 95-99 years, however, the number of female and male finishers remained unchanged. Across years, women (r² = 0.26, P = 0.0090) and men (r² = 0.31, P = 0.0035) reduced their race times. Women and men in age group 75-79 years improved race times. In age groups 80-84 to 90-94 years, women and men were not able to reduce race times. In summary, participation increased and performance improved in female and male marathoners competing in age groups 75-79 to 95-99 years where the largest increases in participation and the largest improvements in performance were found in women and men in age group 75-79 years.

One hundred and fifty years of sprint and distance running - Past trends and future prospects.

Sprint and distance running have experienced remarkable performance improvements over the past century. Attempts to forecast running performances share an almost similarly long history but have relied so far on relatively short data series. Here, we compile a comprehensive set of season-best performances for eight Olympically contested running events. With this data set, we conduct (1) an exponential time series analysis and (2) a power-law experience curve analysis to quantify the rate of past performance improvements and to forecast future performances until the year 2100. We find that the sprint and distance running performances of women and men improve exponentially with time and converge at yearly rates of 4% ± 3% and 2% ± 2%, respectively, towards their asymptotic limits. Running performances can also be modelled with the experience curve approach, yielding learning rates of 3% ± 1% and 6% ± 2% for the women's and men's events, respectively. Long-term trends suggest that: (1) women will continue to run 10-20% slower than men, (2) 9.50 s over 100 m dash may only be broken at the end of this century and (3) several middle- and long-distance records may be broken within the next two to three decades. The prospects of witnessing a sub-2 hour marathon before 2100 remain inconclusive. Our results should be interpreted cautiously as forecasting human behaviour is intrinsically uncertain. The future season-best sprint and distance running performances will continue to scatter around the trends identified here and may yield unexpected improvements of standing world records.

My patient wants to perform strenuous endurance exercise. What's the right advice?

Prolonged strenuous endurance exercise (SEE) such as marathon running has recently been associated with potential deleterious cardiac effects, particularly increased risk of atrial fibrillation (AF). This topic is medically important due to the increasing number of participants in SEE events lasting several hours, including older people. The aim of this narrative review is to provide a summary of the evidence available on SEE and related issues such as cardiovascular mortality, AF, potential cardiac remodeling, cardiovascular events during exertion, or the need for pre-participation screening (with a special focus on beginners). This type of information can help physicians giving advice to their patients and the general public regarding safe SEE practice.

Running shoes and running injuries: mythbusting and a proposal for two new paradigms: 'preferred movement path' and 'comfort filter'.

In the past 100 years, running shoes experienced dramatic changes. The question then arises whether or not running shoes (or sport shoes in general) influence the frequency of running injuries at all. This paper addresses five aspects related to running injuries and shoe selection, including (1) the changes in running injuries over the past 40 years, (2) the relationship between sport shoes, sport inserts and running injuries, (3) previously researched mechanisms of injury related to footwear and two new paradigms for injury prevention including (4) the 'preferred movement path' and (5) the 'comfort filter'. Specifically, the data regarding the relationship between impact characteristics and ankle pronation to the risk of developing a running-related injury is reviewed. Based on the lack of conclusive evidence for these two variables, which were once thought to be the prime predictors of running injuries, two new paradigms are suggested to elucidate the association between footwear and injury. These two paradigms, 'the preferred movement path' and 'the comfort filter', suggest that a runner intuitively selects a comfortable product using their own comfort filter that allows them to remain in the preferred movement path. This may automatically reduce the injury risk and may explain why there does not seem to be a secular trend in running injury rates.

Performance and Age of the Fastest Female and Male 100-KM Ultramarathoners Worldwide From 1960 to 2012.

The purpose of this cross-sectional study was to investigate the change in 100-km running performance and in the age of peak performance for 100-km ultramarathoners. Age and running speed of the annual fastest women and men in all 100-km ultramarathons held worldwide between 1960 and 2012 were analyzed in 148,017 finishes with 18,998 women and 129,019 men using single, multivariate, and nonlinear regressions. Running speed of the annual fastest men increased from 8.67 to 15.65 km.h(-1) and from 8.06 to 13.22 km.h(-1) for the annual fastest women. For the annual 10 fastest men, running speed increased from 10.23 ± 1.22 to 15.05 ± 0.29 km.h(-1) (p < 0.0001) and for the annual 10 fastest women from 7.18 ± 1.54 to 13.03 ± 0.18 km.h(-1) (p < 0.0001). The sex difference decreased from 56.1 to 16.3% for the annual fastest finishers (p < 0.0001) and from 46.7 ± 8.7% to 14.0 ± 1.2% for the annual 10 fastest finishers (p < 0.0001). The age of the annual fastest men increased from 29 to 40 years (p = 0.025). For the annual fastest women, the age remained unchanged at 35.0 ± 9.7 years (p = 0.469). For the annual 10 fastest women and men, the age remained unchanged at 34.9 ± 3.2 (p = 0.902) and 34.5 ± 2.5 years (p = 0.064), respectively. To summarize, 100-km ultramarathoners became faster, the sex difference in performance decreased but the age of the fastest finishers remained unchanged at ∼ 35 years. For athletes and coaches to plan a career as 100-km ultramarathoner, the age of the fastest female and male 100-km ultramarathoners remained unchanged at ∼ 35 years between 1960 and 2012 although the runners improved their performance over time.

Changes in body size and physical characteristics of South African under-20 rugby union players over a 13-year period.

This study compared changes in the body size and physical characteristics of South African under-20 rugby union players over a 13-year period. A total of 453 South African under-20 players (forwards: n = 256 and backs: n = 197) underwent measurements of body mass, stature, muscular strength, endurance, and 10- and 40-m sprint times. A 2-way analysis of variance was used to determine significant differences for the main effects of position (forwards vs. backs) and time (1998-2010). The pooled data showed that forwards were significantly heavier (22%), taller (5%), and stronger (18%) than the backs. However, when 1 repetition maximum strength scores were adjusted for body mass, backs were stronger per kg body mass. Stature did not change over the 13-year period for both groups. There were, however, significant increases in muscular strength (50%), body mass (20%), and muscular endurance (50%). Furthermore, an improvement in sprint times over 40 (4%) and 10 m (7%) was evident over the period of the study. In conclusion, the players became heavier, stronger, taller, and improved their upper-body muscular endurance over the 13 years of the study. Furthermore, sprint times over 10 and 40 m improved over the same time period despite the increase in body mass. It can be speculated that the changes in physical characteristics of the players over time are possibly a consequence of (a) adaptations to the changing demands of the game and (b) advancements in training methods.