The International Fitness Scale (IFIS): A valid tool to assess physical fitness in French children.

BACKGROUND: The need for monitoring regularly physical fitness in youth is well established for public health issues. The aim of this study was to assess the validity and reliability of the International Fitness Scale questionnaire (IFIS) to assess physical fitness in French children in the school context. METHODS: A sample of 2 060 children (1054 boys), aged 10.6 ± 0.9 years, participated in the validation study while an independent sample of 366 children (175 boys), aged 9 to 11 years, participated in the assessment of reliability. Physical fitness was measured by a self-report of 5 questions with a 5-point Likert-scale (from very poor to very good) (IFIS), and also measured objectively by 4 field tests: cardiorespiratory fitness, muscular strength, speed/agility and flexibility. For the test-retest reliability assessment, children were instructed to complete the questionnaire twice, 1 week apart. RESULTS: For all physical fitness components studied, children reporting a good or a very good physical fitness in the IFIS had better results in objective measurements of physical fitness tests compared to children reporting a very poor to an average physical fitness (p<0.001) without or with adjustments for sex, age and weight status. The reliability coefficients were acceptable for all components of physical fitness (0.59-0.72). CONCLUSIONS: These results suggest that IFIS appears to be a useful instrument for teachers to estimate physical fitness levels of French children, possibly on a large scale.

Cardiorespiratory fitness has declined among French children since 1999, although the decline appears to be getting smaller.

BACKGROUND: Cardiorespiratory fitness (CRF) is a strong marker of current and future health. The aim of this study was to assess the national temporal trends in CRF for French children and adolescents between 1999 and 2022. METHODS: CRF data were obtained from several cross-sectional studies on 15 420 (51.1% boys) French children and adolescents aged 9-16 years between 1999 and 2022. The 20-m shuttle run test (20mSRT) estimated CRF. Body mass index (BMI) was calculated from measured height and body mass, with BMI z-scores (BMIz) calculated using WHO growth curves. The 20mSRT results were corrected for protocol and converted to z-scores (20mSRTz) using international sex- and age-specific norms. With additional adjustment for BMIz, temporal trends in mean 20mSRT performance (20mSRTz) were estimated using linear regression, with the distance max (Dmax) method used to locate a breakpoint and linear segments fitted to points below and above the breakpoint. Trends in distributional characteristics were assessed visually and described as the ratio of the coefficients of variation (CVs). RESULTS: After adjustment for protocol, age, sex, and BMIz, a large decline in mean 20mSRT performance (trend per decade (95% CI): -1.42 SDs (-1.45, -1.39) or -18.4% (95% CI: -18.8, -18.0)) between 1999 and 2022 was found. Dmax located a breakpoint for the two-linear-segment model in year 2010. There was a large decline in mean 20mSRT performance pre-2010 (trend per decade (95% CI): -2.31 SDs (-2.39, -2.24)), which reduced 0.06-fold to a negligible decline post-2010 (trend per decade (95% CI): -0.15 SD (-0.20, -0.10)). We also found that the trend in mean 20mSRT performance was not uniform across the population distribution. Between 1999 and 2022, there was a small trend in distributional asymmetry, with slightly smaller declines experienced by the high performers (above the 75th percentile). CONCLUSIONS: Our data suggest a large decline in the 20mSRT performance of French children and adolescents since 1999. This declining trend seems to have diminished considerably since 2010. Such declines in CRF could translate into declines in health status. Although a slowing in the declining trend in CRF in recent years is encouraging, more data are needed to confirm these findings.

Impact of long-lasting moderate-intensity stage cycling event on cardiac function in young female athletes: A case study.

PURPOSE: Effects of intense and/or prolonged exercise have been studied extensively in male athletes. Nevertheless, data are scare on the effect of long duration events on cardiac function in female athletes. Our aim was to investigate the effect of a long-lasting moderate-intensity stage cycling event on cardiac function of young female athletes. METHODS: Seven well-trained female cyclists were included. They completed a cycling event of 3529 km on 23 days. All underwent an echocardiography on 6 time-points (baseline and at the arrival of day (D) 3, 7, 12, 13 and 23). Cardiac function was assessed by conventional echocardiography, tissue Doppler imaging and speckle tracking techniques. Daily exercise load was determined by heart rate (HR), power output and rate of perceived exertion data (RPE, Borg scale). RESULTS: All stages were mainly done at moderate intensity (average HR: 65% of maximal, average aerobic power output: 36% of maximal, average RPE: 4). Resting HR measured at the time of echocardiography did not vary during the event. Resting cardiac dimensions did not significantly change during the 23 days of cycling. No significant modification of cardiac function, whatever the studied cavity, were observed all along the event. CONCLUSION: The results suggest that, in the context of our case study, the long-lasting moderate-intensity stage cycling event was not associated with cardiac function alteration. Nevertheless, we must be careful in interpreting them due to the limits of an underpowered study.

Exercise-Induced Cardiac Fatigue in Soldiers Assessed by Echocardiography.

Background: Echocardiographic signs of exercise-induced cardiac fatigue (EICF) have been described after strenuous endurance exercise. Nevertheless, few data are available on the effects of repeated strenuous exercise, especially when associated with other constraints as sleep deprivation or mental stress which occur during military selection boot camps. Furthermore, we aimed to study the influence of experience and training level on potential EICF signs. Methods: Two groups of trained soldiers were included, elite soldiers from the French Navy Special Forces (elite; n = 20) and non-elite officer cadets from a French military academy (non-elite; n = 38). All underwent echocardiography before and immediately after exposure to several days of uninterrupted intense exercise during their selection boot camps. Changes in myocardial morphology and function of the 4 cardiac chambers were assessed. Results: Exercise-induced decrease in right and left atrial and ventricular functions were demonstrated with 2D-strain parameters in both groups. Indeed, both atrial reservoir strain, RV and LV longitudinal strain and LV global constructive work were altered. Increase in LV mechanical dispersion assessed by 2D-strain and alteration of conventional parameters of diastolic function (increase in E/e' and decrease in e') were solely observed in the non-elite group. Conventional parameters of LV and RV systolic function (LVEF, RVFAC, TAPSE, s mitral, and tricuspid waves) were not modified. Conclusions: Alterations of myocardial functions are observed in soldiers after uninterrupted prolonged intense exercise performed during selection boot camps. These alterations occur both in elite and non-elite soldiers. 2D-strain is more sensitive to detect EICF than conventional echocardiographic parameters.

Daily fatigue-recovery balance monitoring with heart rate variability in well-trained female cyclists on the Tour de France circuit.

OBJECTIVES: This study aimed to analyze the daily heart rate variability (HRV) in well-trained female cyclists during the 2017 Tour de France circuit and to relate it to the load and perceived exertion response. METHODS: Ten female cyclists volunteered to participate in the study. HRV was recorded with a portable heart rate monitor each morning at rest in supine (7 min.) and upright (7 min.) positions, as well as throughout each day's stage. Pre-Tour baseline HRV recordings were made, as well as during the four weeks following completion of the Tour. Exercise daily load was assessed using the training impulse score (TRIMPS). Post-exercise rate of perceived exertion (RPE) was assessed daily using the Borg CR-10 scale. RESULTS: The results show a HRV imbalance, increase of sympathetic and decrease of vagal activities respectively, along the event that correlated with rate of perceived exertion (r = 0.46), training impulse score (r = 0.60), and kilometers (r = 046). The greatest change in HRV balance was observed the days after the greatest relative physical load. Mean heart rate and heart rate variability values returned to their baseline values one week after completion of the event. CONCLUSIONS: Despite incomplete recovery from day-to-day, fatigue is not summative or augmented with each successive stage and its physical load. Just one week is sufficient to restore baseline values. Heart rate and HRV can be used as a tool to strategically plan the effort of female cyclists that participate in multi-stage events.

Asymptomatic bradycardia amongst endurance athletes.

It is established that an intensive training results in a lower average resting heart rate. Management of bradycardia in an athlete can be difficult given the underlying mechanisms are not clearly understood. The authors reviewed the different mechanisms described in the literature, including recent advances in physiology regarding remodeling of ion channels, which may partially explain bradycardia in athletes. Sinus bradycardia amongst athletes, especially endurance focused athletes, is common but difficult to apprehend. The underlying mechanisms are observably of multifactorial origin and likely incompletely elucidated by the current body of knowledge.

Mechanical Dispersion by Strain Echocardiography: A Novel Tool to Diagnose Hypertrophic Cardiomyopathy in Athletes.

BACKGROUND: Previous studies have demonstrated that global longitudinal strain (GLS) is altered in patients with hypertrophic cardiomyopathy (HCM) in comparison with athletes. Nevertheless, these results rely on studies comparing sedentary patients with HCM with healthy athletes. The aims of this study were to confirm these findings in an appropriate group of athletes with HCM and to study the additive value of novel parameters (i.e., mechanical dispersion and exercise GLS). METHODS: Thirty-six athletes with HCM were prospectively included and were compared with 36 sedentary patients with HCM, 36 healthy athletes, and 36 sedentary control subjects of similar age. Athlete groups had similar training duration and HCM groups similar maximal wall thickness. All underwent echocardiography at rest and during submaximal exercise. GLS was assessed; the SD of time to maximal myocardial shortening of longitudinal strain was calculated as a parameter of mechanical dispersion. RESULTS: The HCM sedentary group showed the lowest resting and exercise GLS. Resting GLS was not different between athletes with HCM and the two control groups, but exercise GLS enabled the differentiation of athletes with HCM from healthy athletes. Mechanical dispersion was higher in both HCM groups compared with both control groups at rest and during exercise. Receiver operating characteristic analysis in the athlete groups demonstrated that resting mechanical dispersion (area under the curve = 0.949 ± 0.023) had better ability to identify HCM compared with GLS at rest (area under the curve = 0.644 ± 0.069) (P < .001) or during exercise (area under the curve = 0.706 ± 0.066) (P < .005). CONCLUSIONS: In athletes, normal resting GLS does not rule out the diagnosis of HCM. Mechanical dispersion of longitudinal strain seems to be a promising tool for the diagnosis of HCM in athletes.

Recognition and significance of pathological T-wave inversions in athletes.

BACKGROUND: Pathological T-wave inversion (PTWI) is rarely observed on the ECG of healthy athletes, whereas it is common in patients with certain cardiac diseases. All ECG interpretation guidelines for use within athletes state that PTWI (except in leads aVR, III and V1 and in V1-V4 when preceded by domed ST segment in asymptomatic Afro-Caribbean athletes only) cannot be considered a physiological adaptation. The aims of the present study were to prospectively determine the prevalence of cardiac pathology in athletes presenting with PTWI, and to examine the efficacy of cardiac magnetic resonance in the work-up battery of further examinations. METHODS AND RESULTS: Athletes presenting with PTWI (n=155) were investigated with clinical examination, ECG, echocardiography, exercise testing, 24h Holter ECG, and cardiac magnetic resonance. Cardiac disease was established in 44.5% of athletes, with hypertrophic cardiomyopathy (81%) the most common pathology. Echocardiography was abnormal in 53.6% of positive cases, and cardiac magnetic resonance identified a further 24 athletes with disease. Five athletes (7.2%) considered normal on initial presentation subsequently expressed pathology during follow-up. Familial history of sudden cardiac death and ST-segment depression associated with PTWI were predictive of cardiac disease. CONCLUSIONS: PTWI should be considered pathological in all cases until proven otherwise, because it was associated with cardiac pathology in 45% of athletes. Despite echocardiography identifying pathology in half of these cases, cardiac magnetic resonance must be considered routine in athletes presenting with PTWI with normal echocardiography. Although exclusion from competitive sport is not warranted in the presence of normal secondary examinations, annual follow-up is essential to ascertain possible disease expression.