Prediction of performance in a 100-km run from a simple equation.

This study aimed to identify predictive variables of performance for a 100-km race (Perf100-km) and develop an equation for predicting this performance using individual data, recent marathon performance (Perfmarathon), and environmental conditions at the start of the 100-km race. All runners who had performed official Perfmarathon and Perf100-km in France, both in 2019, were recruited. For each runner, gender, weight, height, body mass index (BMI), age, the personal marathon record (PRmarathon), date of the Perfmarathon and Perf100-km, and environmental conditions during the 100-km race (i.e., minimal and maximal air temperatures, wind speed, total amount of precipitation, relative humidity and barometric pressure) were collected. Correlations between the data were examined, and prediction equations were then developed using stepwise multiple linear regression analyses. Significant bivariate correlations were found between Perfmarathon (p<0.001, r = 0.838), wind speed (p<0.001, r = -0.545), barometric pressure (p<0.001, r = 0.535), age (p = 0.034, r = 0.246), BMI (p = 0.034, r = 0.245), PRmarathon (p = 0.065, r = 0.204) and Perf100-km in 56 athletes The, 2 prediction equations with larger sample (n = 591) were developed to predict Perf100-km, one including Perfmarathon, wind speed and PRmarathon (model 1, r² = 0.549; standard errors of the estimate, SEE = 13.2%), and the other including only Perfmarathon and PRmarathon (model 2, r² = 0.494; SEE = 14.0%). Perf100-km can be predicted with an acceptable level of accuracy from only recent Perfmarathon and PRmarathon, in amateur athletes who want to perform a 100 km for the first time.

Changes in performances/characteristics of French female runners over the last 12 years.

This study investigated the changes in performance of five official track running distances (800m, 1500m, 3000m, 5000m and 10,000m) and the characteristics of French female runners between 2005 and 2016. 22,839 official track performances were scrutinized. For each performance, the race time, the indication of personal record, age, and performance level were recorded. The main results showed that: (1) the number of French track performances has increased in recent years (except for the 10,000m) and the level of these performances has improved significantly only for the longer distances (5000 and 10,000m), (2) the longest distances were generally performed by older athletes, and (3) the highest percentage of international athletes was for the 10,000m event. These findings may be explained by: (1) the development plan put into place by the Fédération France d'Athlétisme, (2) age-dependent physiological and psychological factors and environmental conditions, and (3) the minima to access the international level.

Convergent Validity and Minimal Clinically Important Difference of the Maugeri Foundation Respiratory Failure Questionnaire (MRF-28) and the Chronic Obstructive Pulmonary Disease-Specific Health-Related Quality of Life questionnaire (VQ11).

Purpose: Short and easy questionnaires have been developed to assess the health-related quality of life (HRQoL) in patients with chronic obstructive pulmonary disease (COPD), such as the Maugeri Foundation Respiratory Failure Questionnaire (MRF-28) and the COPD-specific HRQoL Questionnaire (VQ11). Both are valid, reliable, and sensitive, but their minimal clinically important differences (MCID) are unknown. Consequently, this study aimed to confirm the convergent validities of the MRF-28 and VQ11 and establish their MCID. A retrospective design was used to evaluate the effect of individual home-based pulmonary rehabilitation (PR) in 400 COPD patients. Patients and methods: Exercise tolerance, anxiety and depression based on the Hospital Anxiety and Depression Scale (HADS), and HRQoL using three questionnaires (MRF-28, VQ11, and the Visual Simplified Respiratory Questionnaire: VSRQ) were assessed before and after an individualized home-based PR program (5 sessions of 30-45 mins/week for 8 weeks, including a weekly session supervised by a team member). Results: PR improved all measured variables (p < 0.0001). The correlations were significant (p < 0.0001) between VSRQ and MRF-28 (r = -0.685 at baseline and r = -0.686 after the PR program), and between VSRQ and VQ11 (r = -0.691 at baseline and r = -0.753 after the PR program). Moreover, changes in score (delta between after and before PR program) of VSRQ were also significantly correlated (p < 0.0001) to changes in score of MRF-28 (r = -0.372) and VQ11 (r = -0.423). Last, we calculated MCID of -5.2 and -2.0 units for MRF-28 and VQ11, respectively. Conclusion: The MRF-28 and VQ11 can be used in routine practice to evaluate the effects of PR on the HRQoL of COPD patients, with MCID of -5.2 and -2.0, respectively.

Real-life feasibility and effectiveness of home-based pulmonary rehabilitation in chronic obstructive pulmonary disease requiring medical equipment.

BACKGROUND: Pulmonary rehabilitation (PR) is a key treatment of chronic obstructive pulmonary disease (COPD) but studies are still needed to identify the most pertinent criteria to personalize this intervention and improve its efficacy. OBJECTIVE: This real-life retrospective study compared the effects of home-based PR on exercise tolerance, anxiety, depression, and health-related quality of life (HRQoL) in COPD patients, according to their medical equipment. METHODS: Exercise tolerance, anxiety, depression, and HRQoL were evaluated in 109 patients equipped with long-term oxygen therapy (LTOT), 84 patients with noninvasive ventilation (NIV), 25 patients with continuous positive airway pressure (CPAP), and 80 patients with no equipment (NE), before, just after, and 6 and 12 months after PR. RESULTS: At baseline, the body mass index in the CPAP and NIV groups was higher (p<0.05) than in the other two groups, and the forced expiratory volume in 1 second was lower in the LTOT and NIV groups (p<0.001). All parameters improved after PR in the four groups (p<0.05), but for exercise tolerance, only the 6-minute stepper test showed maintained improvement after 6 and 12 months, whereas the 10 times sit-to-stand and timed up-and-go tests were only improved just after PR. At every time point, exercise tolerance was lower in the LTOT group (p<0.05), with a similar trend in the NIV group. CONCLUSION: Despite differences in the medical equipment to treat COPD, home-based PR showed comparable feasibility, safety, and efficacy in all equipment-based groups. Medical equipment should therefore not be a barrier to home-based PR.

Comparison of Specific Prediction Equations to Estimate Peak Oxygen Uptake in Obese Women.

The aim of the current study was to compare 2 equations to predict peak oxygen uptake (V̇O2peak) in obese women, according to their obesity class. 92 maximal cardiopulmonary exercise testing sets (CPET with initial and subsequent increments set to achieve an exercise duration between 8-12 min) were retrospectively analysed. These CPET were divided into 3 groups according to the women body mass indexes (BMI): class 1 (30 kg.m-2≤BMI<35 kg.m-2, n=22), class 2 (35 kg.m-2≤BMI<40 kg.m-2, n=36) or class 3 (BMI≥40 kg.m-2, n=34). Each participant's V̇O2peak was predicted from 2 prediction equations (from Wasserman et al.'s and Debeaumont et al.'s equations) and compared with the actual V̇O2peak. Moreover, the correlations between these values were studied, and the accuracy of the predictions was analysed. Only predicted V̇O2peak from the Debeaumont et al.'s equation was not significantly different from the actual V̇O2peak in the women in obesity class 3 (p=0.89). Moreover, significant correlation was found between these values (p<0.001, r=0.68). The bias and the 95% limits of agreement represented -3.2±34.0%. In women in obesity class 3, Debeaumont et al.'s equation may be the accurate one to predict V̇O2peak. However, the accuracy of predictions is low. Consequently, to improve this accuracy, new prediction equations for obese women are required according to the obesity class.

Benefits of a regular vs irregular rhythm-based training programme on physical fitness and motor skills in obese girls.

PURPOSE: The aim of the current study was to examine the impact of a physical exercise programme including rhythmic elements (regular and irregular tempos) on physiological variables, motor skills (MS), and jump performances in obese girls. METHODS: Thirty-six obese girls (age: 10.4 ± 0.9 years, body mass: 58.7 ± 4.0 kg, height: 1.37 ± 0.04 m, body mass index: 31.2 ± 2.1) participated in three weekly physical exercise sessions for 6 weeks, with each session consisting of basic fundamental locomotor movements. The participants were divided into two groups: a control group (CG) and an experimental group (EG). CG performed the exercise in a quiet setting (i.e., without rhythmic accompaniment), whereas regular and irregular rhythmic accompaniments were prescribed in EG. The physical exercise programme included three sessions per week for 6 weeks. Each session was composed of three parts: 15 min of warm-up, followed by 40 min of exercises based on basic locomotor movements (i.e., running, hopping, skipping, jumping, leaping, sliding, galloping, throwing, catching, kicking, dribbling, and striking) and then 5 min of stretching. Each exercise was demonstrated by the teacher. Before and after the intervention period, cardiovascular measures (i.e., resting blood pressures, recovery for heart rate and systolic blood pressure, and recovery rate-pressure product) were made and five MS (i.e., running, hopping, leaping, jumping and dribbling) were evaluated in two conditions (i.e., during exercise with regular and irregular tempos). Moreover, performances on vertical jump tests (squat and countermovement jump tests) were measured. RESULTS: EG exhibited greater improvement in MS with a regular tempo (and sometimes an irregular tempo), cardiovascular components, and jump performances. CONCLUSION: These findings demonstrate that physical exercise at various tempos is useful for improving physical fitness, developing MS, and thus probably preventing obesity complications.

Exercise training at the crossover point improves bodily and cardiorespiratory data but not quality of life in women with metabolic syndrome.

BACKGROUND: This study investigated the effects of an exercise program at the intensity corresponding to the crossover point of substrate utilization (COP) on anthropometric measures, health-related quality of life (HRQoL) and cardiorespiratory fitness (i.e., peak oxygen uptake [V̇O2peak] and peak power output [Ppeak]) in women with metabolic syndrome (MetS). METHODS: Nineteen obese and post-menopausal women with MetS (age: 54.8±8.1 years, body mass: 89.0±12.2 kg, Body Mass Index: 34.5±4.0 kg/m2) followed a 12-week program consisting of three 45-minute sessions per week of cycle ergometer exercise. The imposed exercise intensity corresponded to COP. Before and after the program, HRQoL, V̇O2peak and Ppeak were measured and then compared. RESULTS: Body mass (89.0±12.2 vs. 86.2±11.0 kg), Body Mass Index (34.5±4.0 vs. 33.4±3.6 kg/m2), waist (106±10 vs. 100±9 cm) and hip (117±11 vs. 114±11 cm) circumferences, waist-to-hip ratio (0.91±0.07 vs. 0.88±0.07), fat mass (43.3±4.6 vs. 41.9±4.6%), fat-free mass (56.7±4.6 vs. 58.2±4.6%), V̇O2peak (16.6±3.4 vs. 18.1±4.1 mL/min/kg) and Ppeak (102±22 vs. 125±27 W) were significantly improved after the exercise program (P<0.05), but HRQoL showed no significant improvement on any subscale (i.e., physical functioning: performance limitation for physical activities including bathing and dressing, role physical: problems with work or other daily activities, bodily pain, general health, vitality, social functioning, role emotional and mental health; P>0.05). CONCLUSIONS: Although a 12-week exercise program at COP improved anthropometric measures and cardiorespiratory fitness in women with MetS, self-perceived HRQoL did not significantly improve. This finding may be linked to a significant but still insufficient reduction in body mass, probably because COP is too weak exercise intensity to induce important energy expenditure.

Correlation of gas exchange threshold and first muscle oxyhemoglobin inflection point with time-to-exhaustion during heavy-intensity exercise.

BACKGROUND: The twofold aim of the study was to: 1) compare the gas exchange threshold (GET), the first oxyhemoglobin inflection point ([O2Hb]-T), and perceptual threshold as determined during an incremental exercise test, and 2) investigate the link between each threshold and time-to-exhaustion during heavy intensity exercise. METHODS: Fourteen competitive cyclists performed an incremental exercise test to exhaustion on a cycloergometer to determine the different thresholds and peak workload (Wpeak). The participants then performed a sub-maximal constant workload test (90% Wpeak) to exhaustion to determine time-to-exhaustion. The thresholds were identified from: 1) the first breakpoint in the oxygen uptake vs. carbon dioxide output curve (GET), 2) the [O2Hb]-T, and 3) a rating of 13 in perceived exertion (perceptual threshold: RPE13-T). RESULTS: Oxygen uptake at the different thresholds was not significantly different (P>0.05). Moreover, GET and [O2Hb]-T were significantly correlated: 1) to each other (r≥0.79; P≤0.001), and 2) to time-to-exhaustion (r=0.81 and r=0.72, respectively; P<0.01). RPE13-T, however, was not significantly correlated with the time-to-exhaustion (P=0.148). CONCLUSIONS: The anaerobic threshold as identified from GET was concomitant to [O2Hb]-T. Both thresholds were correlated to time-to-exhaustion, and could therefore be used as a performance index in middle-duration events.

Home-based neuromuscular electrical stimulation improves exercise tolerance and health-related quality of life in patients with COPD.

BACKGROUND: This retrospective, observational study of a routine clinical practice reports the feasibility and efficiency of home-based pulmonary rehabilitation (PR), including transcutaneous neuromuscular electrical stimulation (NMES) or usual endurance physical exercise (UEPE), on exercise tolerance, anxiety/depression, and health-related quality of life (HRQoL) in patients with COPD. METHODS: Seventy-one patients with COPD participated in home-based PR with NMES (Group NMES [GNMES]), while 117 patients participated in home-based PR with the UEPEs (Group UEPE [GUEPE]). NMES was applied for 30 minutes twice a day, every day. The endurance exercises in GUEPE began with a minimum 10-minute session at least 5 days a week, with the goal being 30-45 minutes per session. Three upper and lower limb muscle strengthening exercises lasting 10-15 minutes were also proposed to both the groups for daily practice. Moreover, PR in both the groups included a weekly 90-minute session based on an educational needs assessment. The sessions comprised endurance physical exercise for GUEPE, NMES for GNMES, resumption of physical daily living activities, therapeutic patient education, and psychosocial support to facilitate health behavior changes. Before and after PR, functional mobility and physical exercise capacity, anxiety, depression, and HRQoL were evaluated at home. RESULTS: The study revealed that NMES significantly improved functional mobility (-18.8% in GNMES and -20.6% in GUEPE), exercise capacity (+20.8% in GNMES and +21.8% in GUEPE), depression (-15.8% in GNMES and -30.1% in GUEPE), and overall HRQoL (-7.0% in GNMES and -18.5% in GUEPE) in the patients with COPD, regardless of the group (GNMES or GUEPE) or severity of airflow obstruction. Moreover, no significant difference was observed between the groups with respect to these data (P>0.05). CONCLUSION: Home-based PR including self-monitored NMES seems feasible and effective for severely disabled COPD patients with severe exercise intolerance.

Plyometric exercise combined with high-intensity interval training improves metabolic abnormalities in young obese females more so than interval training alone.

The aim of this study was to compare the effects of 12 weeks of high-intensity interval training (HIIT) with the effects of 12 weeks of plyometric exercise combined with HIIT (P+HIIT) on anthropometric, biochemical, and physical fitness data in young obese females. Sixty-eight participants (age, 16.6 ± 1.3 y; body mass, 82.8 ± 5.0 kg; body fat, 39.4% ± 3.3%; body mass index z score, 2.9 ± 0.4) were assigned to 1 of 3 groups: HIIT (2 blocks per session of 6-8 bouts of 30-s runs at 100% velocity at peak oxygen uptake, with 30-s active recovery between bouts at 50%velocity at peak oxygen uptake (n = 23)); P+HIIT (2 blocks per session of 3 different 15-s plyometric exercises with 15-s passive recoveries, totaling 2 min for each plyometric exercise + the same HIIT program (n = 26)); or control (no exercise (n = 19)). Anthropometric (body mass, body mass index z score, body fat, lean body mass, and waist circumference), biochemical (plasma glucose, insulin, leptin and adiponectin concentrations, leptin/adiponectin ratio, and homeostasis model assessment of insulin resistance (HOMA-IR)), physical fitness (peak oxygen uptake, velocity at peak oxygen uptake, squat jump, and countermovement jump performances), and energy intake data were collected. Both training programs improved the anthropometric, biochemical, and physical fitness variables. However, the P+HIIT program induced greater improvements than did the HIIT program in lean body mass (+3.0% ± 1.7%), plasma glucose and leptin concentrations (-11.0% ± 4.7% and -23.8% ± 5.8%, respectively), plasma leptin/adiponectin ratio (-40.9% ± 10.9%), HOMA-IR (-37.3% ± 6.2%), and squat jump performance (22.2% ± 7.5%). Taken together, these findings suggest that adding plyometric exercises to a HIIT program may be more beneficial than HIIT alone in obese female adolescents.

Effect of Performance Level on the Prediction of Middle-Distance-Running Performances Using a Nomogram.

PURPOSE: This study examined the effect of performance level on the validity and accuracy of middle-distance running-performance predictions obtained from the nomogram of Mercier et al in male runners. METHODS: Official French track-running rankings for the 3000-, 5000-, and 10,000-m events from 2006 to 2014 were examined. The performance level was determined from the official reference table of the Fédération Française d'Athlétisme, and the runners were divided in 3 groups (ie, low, moderate, and high levels). Only male runners who performed in the 3 distance events within the same year were included (N = 443). Each performance over any distance was predicted using the nomogram from the 2 other performances. RESULTS: No difference was found in low- and moderate-performance-level athletes (0.02 ≤ effect size [ES] ≤ 0.06, 95% limits of agreement [LoA] ≤ 6%). By contrast, a small difference in high-performance-level athletes (P < .01, 0.23 ≤ ES ≤ 0.45, 95% LoA ≤ 11.6%) was found. CONCLUSION: The study confirms the validity of the nomogram to predict track-running performance with a high level of accuracy, except for male runners with high performance level (ie, national or international). Consequently, the predictions from the nomogram may be used in training programs (eg, to prescribe tempo runs with realistic training velocities) and competitions (eg, to plan realistic split times to reach the best performance).

Reproducibility and Sensitivity of the 6-Minute Stepper Test in Patients with COPD.

The aims of this study were to test the reproducibility of the 6-minute stepper test (6MST), and evaluate its accuracy in detecting improved functional capacity after pulmonary rehabilitation (PR) in patients with chronic obstructive pulmonary disease (COPD). Thirty-five COPD outpatients performed two 6MSTs in the same session, before (6MST1 and 6MST2) and after (6MST3 and 6MST4) PR. The performance, perceived exertion, heart rate and arterial oxygen saturation were measured during each 6MST. The performance was higher during the second 6MST of the same session (before PR: 514 strokes during the 6MST2 > 471 strokes during the 6MST1, and after PR: 559 strokes during the 6MST4 > 508 strokes during the 6MST3; p = 0.04). After PR, 6MST performance was higher than before PR (6MST3 > 6MST1 and 6MST4 > 6MST2; P < 0.01). The bias (the difference in the number of strokes) between the two 6MSTs from the same session (before PR: 6MST2-6MST1 = 42 strokes vs after PR: 6MST4-6MST3 = 52 strokes) was not different (P = 0.34). However, both bias were greater than 0 (P < 0.001). The mean performances for the two 6MSTs of the same session (before PR: 6MST1 and 6MST2 and after PR: 6MST3 and 6MST4) were correlated with the bias between these performances (P < 0.01; r = 0.32). The perceived exertions were lower after PR (P < 0.02). The systematic improvement of performance (8-10%) during the second 6MST of the each session may be explained from the warming of hydraulic jacks of the stepper and/or learning effect. On the other hand, the 6MST seems sufficiently sensitive to detect functional capacity improvements after PR in patients with COPD.

Prediction of peak oxygen uptake from ratings of perceived exertion during a sub-maximal cardiopulmonary exercise test in patients with chronic obstructive pulmonary disease.

PURPOSE: We assessed the validity of predicting peak oxygen uptake ([Formula: see text]O2 peak) from the relationship between oxygen uptake ([Formula: see text]O2) and overall ratings of perceived exertion (RPE) obtained during the initial stages of a cardiopulmonary exercise test (CPET). METHOD: Fifteen healthy participants and 18 patients with chronic obstructive pulmonary disease (COPD) performed a maximal CPET, during which [Formula: see text]O2 and RPE were measured until RPE15. RESULTS: Individual regressions between [Formula: see text]O2 and RPE ≤ 15 were extrapolated to RPE19 to predict [Formula: see text]O2 peak. Mean actual and predicted [Formula: see text]O2 peak were not significantly different in healthy women (18.9 ± 4.1 vs. 20.4 ± 4.5 mL kg(-1) min(-1), respectively) and men (28.9 ± 7.8 vs. 29.7 ± 8.5 mL kg(-1) min(-1), respectively), or in women (15.2 ± 4.7 vs. 15.8 ± 5.0 mL kg(-1) min(-1), respectively) and men (16.2 ± 4.4 vs. 17.4 ± 5.4 mL kg(-1) min(-1), respectively) with COPD (P = 0.067). Moreover, actual and predicted [Formula: see text]O2 peak were highly correlated in healthy participants and COPD patients (r ≥ 0.89; P < 0.001). The bias and 95 % limits of agreement were -1.0 ± 4.0 and -1.0 ± 4.6 mL kg(-1) min(-1) for healthy and COPD participants, respectively. CONCLUSION: [Formula: see text]O2 peak can be predicted with acceptable accuracy in healthy participants and patients with COPD from the individual relationship between [Formula: see text]O2 and RPE ≤ 15.

Influence of sex and specialty on the prediction of middle-distance running performances using the Mercier et al.'s nomogram.

The aim was to test the influence of sex and specialty (3000, 5000 and 10000 m) on the validity of middle-distance running performance predictions obtained from the Mercier et al.'s nomogram. Consequently, we examined all official French track running rankings for the 3000-, 5000- and 10000-m events (men and women) from 2006 to 2012. A scoring table was used to determine the runners' specialties. Only runners who performed in the three distance events within the same year were included (75 women and 400 men). The Mercier et al.'s nomogram was used to predict one running performance from the other two. The results showed no significant difference between actual and predicted running performances (P = 0.77). Female runners had significantly lower performances than male runners (P < 0.001). Specialty did not influence performances (P = 0.11). Very high correlations were found between actual and predicted performances (0.91 < r < 0.99), with the exception of women (r = 0.85) in 5000 m. Moreover, low limits of agreement were obtained for male and female runners, whatever the specialty. These results support the validity of the nomogram to predict running performance in the 3000-, 5000- and 10000-m events for male and female runners, whatever the specialty. The predicted running performances may be used in training programmes (e.g., to prescribe tempo runs) and competitions (e.g., to establish split times).

Prediction of maximal or peak oxygen uptake from ratings of perceived exertion.

Maximal or peak oxygen uptake (V˙O2 max and V˙O2 peak , respectively) are commonly measured during graded exercise tests (GXTs) to assess cardiorespiratory fitness (CRF), to prescribe exercise intensity and/or to evaluate the effects of training. However, direct measurement of CRF requires a GXT to volitional exhaustion, which may not always be well accepted by athletes or which should be avoided in some clinical populations. Consequently, numerous studies have proposed various sub-maximal exercise tests to predict V˙O2 max or V˙O2 peak . Because of the strong link between ratings of perceived exertion (RPE) and oxygen uptake (V˙O2), it has been proposed that the individual relationship between RPE and V˙O2 (RPE:V˙O2) can be used to predict V˙O2 max (or V˙O2 peak) from data measured during submaximal exercise tests. To predict V˙O2 max or V˙O2 peak from these linear regressions, two procedures may be identified: an estimation procedure or a production procedure. The estimation procedure is a passive process in which the individual is typically asked to rate how hard an exercise bout feels according to the RPE scale during each stage of a submaximal GXT. The production procedure is an active process in which the individual is asked to self-regulate and maintain an exercise intensity corresponding to a prescribed RPE. This procedure is referred to as a perceptually regulated exercise test (PRET). Recently, prediction of V˙O2max or V˙O2 peak from RPE:V˙O2 measured during both GXT and PRET has received growing interest. A number of studies have tested the validity, reliability and sensitivity of predicted V˙O2 max or V˙O2 peak from RPE:V˙O2 extrapolated to the theoretical V˙O2 max at RPE20 (or RPE19). This review summarizes studies that have used this predictive method during submaximal estimation or production procedures in various populations (i.e., sedentary individuals, athletes and pathological populations). The accuracy of the methods is discussed according to the RPE:V˙O2 range used to plot the linear regression (e.g., RPE9­13 versus RPE9­15 versus RPE9­17 during PRET), as well as the perceptual endpoint used for the extrapolation (i.e., RPE19 and RPE20). The V˙O2 max or V˙O2 peak predictions from RPE:V˙O2 are also compared with heart rate-related predictive methods. This review suggests that V˙O2 max (or V˙O2 peak ) may be predicted from RPE:V˙O2 extrapolated to the theoretical V˙O2 max (or V˙O2 peak) at RPE20 (or RPE19). However, it is generally preferable to (1) extrapolate RPE:V ˙ O 2 to RPE19 (rather than RPE20); (2) use wider RPE ranges (e.g. RPE ≤ 17 or RPE9­17) in order to increase the accuracy of the predictions; and (3) use RPE ≤ 15 or RPE9­15 in order to reduce the risk of cardiovascular complications in clinical populations.

Effect of additional respiratory muscle endurance training in young well-trained swimmers.

While some studies have demonstrated that respiratory muscle endurance training (RMET) improves performances during various exercise modalities, controversy continues about the transfer of RMET effects to swimming performance. The objective of this study was to analyze the added effects of respiratory muscle endurance training (RMET; normocapnic hyperpnea) on the respiratory muscle function and swimming performance of young well-trained swimmers. Two homogenous groups were recruited: ten swimmers performed RMET (RMET group) and ten swimmers performed no RMET (control group). During the 8-week RMET period, all swimmers followed the same training sessions 5-6 times/week. Respiratory muscle strength and endurance, performances on 50- and 200-m trials, effort perception, and dyspnea were assessed before and after the intervention program. The results showed that ventilatory function parameters, chest expansion, respiratory muscle strength and endurance, and performances were improved only in the RMET group. Moreover, perceived exertion and dyspnea were lower in the RMET group in both trials (i.e., 50- and 200-m). Consequently, the swim training associated with RMET was more effective than swim training alone in improving swimming performances. RMET can therefore be considered as a worthwhile ergogenic aid for young competitive swimmers. Key PointsRespiratory muscle endurance training improves the performance.Respiratory muscle endurance training improves the ventilatory function parameters, chest expansion, respiratory muscle strength and endurance.Respiratory muscle endurance training decreases the perceived exertion and dyspnea.Respiratory muscle endurance training can be considered as a worthwhile ergogenic aid for young competitive swimmers.

Estimated time limit: a brief review of a perceptually based scale.

The ability to predict performance is of great interest for athletes and coaches. It is helpful for the selection of athletes to a team, the prescription of individualized training and the determination of the optimal pacing strategy. However, it is often difficult to judge the time to exhaustion without maximal exercise testing, which is often difficult to schedule during a competitive season. Consequently, the purpose of this review is to present a recent tool based on subjective prediction of time to exhaustion than can be achieved without requiring a maximal effort. This tool is the estimated time limit (ETL) scale. This review summarizes all experimentations that have studied the ETL scale. These studies suggest that the ETL scale may be used to predict time to exhaustion.

Prediction of time to exhaustion in competitive cyclists from a perceptually based scale.

Prediction of time to exhaustion in competitive cyclists from a perceptually based scale. We have tested the validity of the estimated time limit (ETL) scale to predict an exhaustion time (T(lim)) from values stemming from incremental and randomized constant workloads tests on a cycle ergometer. Twenty-five cyclists performed 1 continuous incremental test, 1 discontinuous test with randomized workloads, and 1 constant power output test at 90% of maximal aerobic power (MAP) to exhaustion. Estimated time limits at 90% MAP during the incremental test and the test with randomized workloads were calculated from exponential relationships between power and ETL using the same 4 workloads. Real measured T(lim) during the constant power output test was converted into ETL values (called measured ETL). The differences between the calculated and measured ETLs were examined. Estimated time limits calculated at 90% MAP during the incremental and randomized tests corresponded to 14 minutes 56 seconds and 10 minutes 14 seconds, whereas measured ETL was equal to 11 minutes 19 seconds ± 3 minutes 40 seconds. The results showed a nonsignificant difference between calculated and measured ETLs. However, the mean differences between the measured ETL values during the constant test performed at the same intensity were -1.3 ± 2.9 and 0.3 ± 3.0 for the incremental and the randomized constant workloads tests, respectively. Consequently, the use of ETL calculated at 90% MAP during the test with randomized constant workloads may be preferable to predict the accurate T(lim). Moreover, it would seem that high-level cyclists, who were more consciously attuned to their bodies and their own effort sense, were more accurate in their prediction than low-level cyclists. It is concluded that the randomized constant workloads test that is both shorter and less strenuous would be more convenient for high-level athletes.

Precision in the prediction of middle distance-running performances using either a nomogram or the modeling of the distance-time relationship.

The purpose was to determine the levels of precision in the prediction of middle-distance performances in running using the modeling of the distance-time relationship and a nomogram. Official French running rankings for the men's 3,000; 5,000; and 10,000 m were scrutinized from 1996 to 2007. Only runners who competed over the 3 distances within the same year were included (n = 100). The distance-time relationship was modeled using a linear 2-parameter model from the plot of 2 performances to predict a third one. The nomogram of Mercier was also used to predict 1 performance from the use of the other 2. Actual and predicted performances were significantly different, except for the 5,000- and 10,000-m performances predicted from the nomogram (p > 0.05). Effect sizes (ESs) were lower when the performance was predicted by the nomogram (-0.25 < ES < 0.05) compared with the linear 2-parameter model (-0.99 < ES < 0.47). The predicted performances were significantly correlated to the actual performances (r > 0.46; p < 0.01). The bias ± limits of agreement for the 3,000-; 5,000-; and 10,000-m performances were 1.0 ± 12.8, -0.1 ± 6.9, and 0.1 ± 20.8% and 3.7 ± 15.5, -1.4 ± 6.2, and 2.5 ± 10.6% for prediction from the nomogram and distance-time relationship, respectively. Although the modeling of the distance-time relationship does not enable middle-running performances to be accurately predicted, the precision in the predictions from the nomogram suggests that the nomogram may be used to prescribe adapted training intensities and determine the optimal strategy during the race.