Analysis of the 10-day ultra-marathon using a predictive XG boost model

OBJECTIVE

Ultra-marathon running races are held as distance-limited or time-limited events, ranging from 6 h to 10 days. Only a few runners compete in 10-day events, and so far, we have little knowledge about the athletes' origins, performance, and event characteristics. The aim of the present study was to investigate the origin and performance of these runners and the fastest race locations. A machine learning model based on the XG Boost algorithm was built to predict running speed from the athlete´s age, gender, country of origin, country where the race takes place, the type of race and the kind of running surface. The model explainability tools were then used to investigate how each independent variable would influence the predicted running speed.

RESULTS

The model rated the origin of the athlete as the most important predictor, followed by age group, running on dirt path, gender, running on asphalt, and event location. Running on dirt path led to a significant reduction of running speed, while running on asphalt showed faster running speeds compared to other surfaces. Most athletes came from USA, followed by Russia, Germany, Ukraine, the Czech Republic, and Slovakia. Most of the runners competed in USA. The fastest 10-day runners were from Finland and Israel. The fastest 10-day races were held in Greece.

CONCLUSIONS

Most 10-day runners originated from USA, but the fastest runners originate from Finland and Israel. The fastest race courses were in Greece. Running on dirt paths leads to a significant reduction in running speed while running on asphalt leads to faster running speeds.

Olympic cycle periodicity in women's long and triple jumping performance between 1996 and 2019

Performance variability is present in a series of competition results in athletics. Some of the variability is random and some can be attributed to factors such as the environment and changes in the level of physical, mental, and technical states of the athlete. Changes in the state of the athlete may be due to the competition schedule. It has been shown that there is periodicity in performance aligned with the seasonal competition schedule in athletics and with the Olympic cycle in pooled athletics data dating from 1896 to 2008. We investigated whether Olympic cycle periodicity was present in modern era long and triple jumping in elite men and women. Top 50 performances per year in the horizontal jumps in men and women from 1996 to 2019 were used. Each performance was normalized to the best result from the previous Olympic year. Two-way ANOVAs revealed significantly lower mean normalized performances in top ten women compared to top ten men (p < 0.001) in both jumps. In both jumps, ten top-performing women also showed decreases between the Olympic year mean normalized performances and the 1st year following (Long Jump: p = 0.022, Triple Jump: p = 0.008). In triple jump, the decrease in performance was also found in the second year following the Olympics. Performances deciles ranked from 11th to 50th place showed a similar pattern in women's triple jump but only for ranks 11 to 20 in the women's long jump. The findings suggest that periodicity driven by the Olympic cycle exists in women's long and triple jump at the elite level.

Corrective adjustment methods for relative age effects on French young swimmers' performances

BACKGROUND

This study aimed to identify a Relative Age Effect (RAE) among French young swimmers and apply corrective adjustment procedures to rebalance performances according to categories and events.

METHODS

5,339,351 performances of French swimmers aged 10 to 18 were collected between 2000 and 2019. Birth quarters distribution was examined according to competitiveness level ('All', 'Top50%', 'Top25%' and 'Top10%'), event and age category. A linear relationship between the distribution of performances and calendar days provides a calibration coefficient allowing to rebalance performances by considering the effect of RAE for each event. Then, adjusted performances are recalculated using this coefficient, the initial performance and the relative age.

RESULTS

Proportion of swimmers born in the first quarter was higher than the proportion of those born in the last quarter for all events and strokes (p < 0.01). RAE increases with the competitiveness level for all events. Indeed, among 'All' 12 years old 50m freestyle swimmers, the proportion born in the first quarter is 30.9% vs 19.2% in the fourth quarter, while among the "Top10%", 47.5% were born in the first quarter vs 10.3% in the last one. (p-value < 0.01). In average, each day represents a gap of 0.008 second, resulting in a difference of almost 3 seconds over a year. This tool is validated by comparing swimmers who have performed at least twice in a season. It provides a day by day rebalancing method for all swimming events and age categories.

CONCLUSIONS

Relative age effect is present among French young male and female swimmers, and is strengthened by competitiveness level. A new corrective adjustment procedure to rebalance performances considering categories and events is proposed and validated. By applying such a tool, we are able to reveal the full potential of swimmers and make it possible to compare them at the same relative age.

Echocardiographic Assessment of Left Ventricular Function 10 Years after the Ultra-Endurance Running Event Eco-Trail de Paris® 2011

Background: Regular and moderate physical activity is beneficial for physical and mental health, resulting in an increase in life expectancy for both sexes. From a cardiovascular point of view, although the benefits of regular moderate physical exercise have been established, the long-term effects of repeated ultra-endurance running events are still unknown. Hypothesis: The aim of our study is to evaluate the 10-year evolution of the parameters of the left ventricular systolic and diastolic functions of amateur subjects regularly practising ultra-endurance running events using resting echocardiography. Study design: Cross-sectional study. Level of evidence: Level 3—non-randomized controlled cohort/follow-up study. Methods: The 66 participants who participated in the 2011 edition of the Eco-Trail de Paris® were contacted by e-mail. Demographic data, sports practice, and the results of an echocardiography scan carried out during the year 2021 evaluating left ventricular systolic and diastolic function variables were collected. Echographic variables from 2011 and 2021 were compared using the paired Student’s t-test. Results: Forty-six (70%) participants responded positively. Twenty (30%) participants could not be reached and were not analysed. Of the 46 respondents, 42 (91%) provided data from a trans-thoracic cardiac ultrasound performed in 2021. Over the past 10 years, the participants reported having completed an average of 4 ± 2 ultra-trails per year. No significant differences were observed between left ventricular diastolic and systolic echocardiographic parameters between the years 2011 and 2021. Conclusions: Among amateur participants, long-distance running is not associated with an alteration in the echocardiographic parameters of resting left ventricular systolic and diastolic function after 10 years of practice. Clinical relevance: Long-term long-distance running practice is not associated with left ventricular cardiac function alteration. These results suggest a potential adaptation role of the cardiovascular system to regular and moderate long-distance running practice.

Physical exercise increases global and gene-specific (interleukin-17 and interferon-γ) DNA methylation in lymphocytes from aged women

NEW FINDINGS

What is the central question of this study? Is lymphocyte DNA methylation differentially modulated by resistance training and aerobic exercise in older women? What is the main finding and its importance? The practice of resistance training led to an increased global DNA methylation in lymphocytes. The exercise-induced increase of inflammatory genes methylation may be associated with immune function impairment during ageing.

ABSTRACT

Ageing-induced increase in inflammatory gene expression through a reduction in DNA methylation might contribute to chronic diseases. Regular physical exercise practices, in turn, are associated with a decrease in the incidence of inflammatory diseases. We herein evaluated the effects of three exercise modalities on lymphocyte global and gene-specific (interferon γ (IFN-γ) and interleukin 17A (IL-17A) DNA methylation in aged women (68 ± 7.5 years). This cross-sectional study included 86 women, divided into four groups according to the physical exercise practice: 20 were practicing resistance training (RT); 24 were practicing water aerobics exercise (W); 22 were practicing water aerobics and resistance exercise (RWT), and 20 did not practice any physical exercise (CON). We evaluated volunteer functional capability using the Timed Up and Go (TUG) test, global lymphocyte DNA methylation by enzyme-linked immunosorbent assay, IFN-γ and IL-17A methylation by qPCR and CD4⁺ IFN-γ⁺ and CD4⁺ IL-17⁺ cell percentage by flow cytometry. The three physically exercised groups performed functional capability tests in a shorter period and showed a higher global lymphocyte DNA methylation and methylated CpGs of IL-17A and IFN-γ promoter regions than the control group. The practice of resistance training (RT and RWT groups) lead to high global DNA methylation. The combination of resistance training and aerobic exercise led to the increase of lymphocyte IL-17A and IFN-γ gene methylation induced by each separately. However, the percentage of IFN-γ⁺ and IL-17⁺ cells was lower only in the RT group. The exercise-induced increase of inflammatory-gene methylation may be associated with gene expression changes and immune function impairment during ageing.

Involvement in Multiple Race Events Among International Para and Non-disabled Swimmers

International elite Para swimmers form a large portion of the overall multi-medalist winning population. For the highest performing Para swimmers, world class performances were achieved across different strokes. The aim of this study was to quantify the level of involvement across different events and to examine this in relation to the level of performance. The performances in swimming speed of the top 100 females and males for both Para- and non-disabled swimmers were collected in 11 race events between 2009 and 2019 (4,400 performances for 307 Para females and 365 Para males, 605 non-disabled females, and 715 non-disabled males). We tallied the number of events in which each swimmer was involved. Swimmers were grouped according to the total number of race events in which they participated. Then the association between involvement and level of performance was investigated. Para swimmers with impairment from classes seven to 14 were involved in a range of race events across different strokes. The most common combination for both Para and non-disabled athletes was over similarly distanced races of the same stroke (50 and 100 m freestyle). The more race events in which Para swimmers involved, the higher the level of performance that was achieved. This trend can partially be explained by the less concentrated competition pool for Para swimmers compared to able-bodied swimmers. Para swimmers with minimal and no physical impairment perform in multiple race events more often than able-bodied swimmers. Fewer Para swimmers at the international level and a less concentrated competition pool could explain these differences.

Spring-loaded body mass equivalent horizontal reactive countermovement jump ground contact and flight times, but not peak forces, are comparable to vertical jumping

Horizontal (cylinder-based) sledge jumping has been shown to ameliorate multi-system deconditioning induced by long-term bed-rest. However, biomechanics differ from 1 g vertical jumping, in particular prolongation of ground contact times (GCT), reduction of peak force, rate of force development (RFD) (and presumably stretch shortening cycle [SSC] efficacy) and stiffness, whilst also requiring relatively complex equipment. Thus, we sought to determine if horizontal spring-loaded countermovement jumps were more analogous to vertical jumping. 9 healthy (5 female) subjects (27 ± 7yrs; 169.0 ± 5.3 cm; 63.6 ± 2.6 kg) performed 10 reactive countermovement jumps vertically, and horizontally (randomized) when lay on a spring-loaded carriage performed against loading (at lift-off) equivalent (±6%) to their body weight. Jump kinetics, kinematics and lower limb/trunk electromyographic activity were compared between conditions (paired t-tests). Mean flight and GCTs did not differ, however, peak jump height (p = 0.003; d = -0.961) was greater when jumping horizontally. In contrast, ground reaction forces (zGRF) during take-off (p < 0.001; d = 1.645) and landing (p = 0.002; d = 1.309), peak acceleration (p = 0.001; d = 1.988), leg stiffness (p = 0.001; d = 2.371) and RFD (p = 0.023; d = 1.255) were lower horizontally. Mean rectus femoris activity was lower during landing (p = 0.033; d = 0.691) when horizontal, but did not differ during either take-off or land-lift. Mean medial gastrocnemius activity was significantly (p = 0.018; d = 0.317) lower during horizontal take-off. Spring-loading (1 g at take-off) maintained short GCTs and flight times presumably maintaining muscle SSC efficacy in a manner that appears intuitive (in young active subjects), simple, robust and potentially compatible with spaceflight. Whether appropriate jump characteristics can be achieved in older subjects and in μg/hypogravity needs to be determined. However, greater jump height, lower peak zGRF, RFD and leg stiffness along with reduced lower limb and trunk muscle activity suggests that 1 g at take-off is insufficient to replicate vertical jump biomechanics. Thus, further investigation is warranted to optimize, and evaluate spring-loaded jumping as a gravity-independent multi-systems countermeasure on Earth, and in Space.

The age-performance relationship in the general population and strategies to delay age related decline in performance

The age-performance relationship describes changes in the organism's structural and functional capabilities over the course of the lifespan. The typical, empirical pattern is an asymmetrical inverted-U shape association with peak capacity occurring early in life. This process is well described in the literature, with an increasing interest in features that characterize this pattern, such as the rate of growth, age of peak performance, and rate of decline with aging. This is usually examined in cohorts of individuals followed over time with repeat assessments of physical or cognitive abilities. This framework ought to be integrated into public health programs, embedding the beneficial (such as physical or cognitive training) or adverse effects (such as chronic diseases or injuries) that respectively sustain or limit capabilities. The maintenance of physical or cognitive performances at older ages would result in both optimal health and promote resistance to disabling conditions and chronic diseases, such as obesity and type 2 diabetes. The causes of accelerated degeneration of health optima are mainly: sedentary and unhealthy lifestyles -including poor nutrition-, exposure to environmental pollutants, and heterogeneity in aging. Better knowledge of optima, compatible with or required for good health, should also allow for establishing ideal conditions for longevity.