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To date, no studies have proposed specific taxonomies of stressors and coping strategies used to manage them by ultra trail runners in races longer than 200 miles, with existing research focusing on significantly shorter distances an then on challenges that could be of a different nature. The aim of this study was to fill this gap by developing specific taxonomies that would group both the stressors encountered and the coping strategies into distinct conceptual categories. Furthermore, to observe in a real competition if these taxonomies allows the evaluation of the coping strategies used by athletes. Two Focus Groups composed of experts on the topic proposed provisional classifications, which were analysed using Applied Thematic Analysis. Three distinct Draft Taxonomies were identified: typical stressors, functional and dysfunctional coping strategies used by athletes during competitions. A critical comparison between the provisional taxonomies and literature led to the development of three definitive taxonomies. In a second phase, to verify whether the taxonomies reflected the real experiences of runners, seven participants in a 280-mile race were interviewed daily during the event. Their responses regarding the stressors and the strategies they had implemented to deal with them were recorded. Expert panelists categorized the transcribed responses according to the proposed taxonomies. The concordance of the judgments, verified with the Fleiss K, was considered a measure of the taxonomies’ ability to capture real experiences. Results confirmed substantial agreement between the raters regarding both the stressors (K = 0.711, p < 0.001) and the coping strategies (K = 0.73, p < 0.001). The analysis of the proportion between the use of functional and dysfunctional strategies proved to be high (between 0.66 and 1) among athletes who completed more than 50% of the race. The taxonomies were found to effectively described athletes’ race experiences, revealing context-specific coping strategies likely developed through years of practice.

Cold temperatures (<−15°C) increase exercise‐induced bronchoconstriction (EIB), while hypoxic‐induced hyperventilation exacerbates respiratory muscle fatigue for a given exercising task. This study aimed to determine the individual and combined effects of cold and normobaric hypoxia on the respiratory system responses to high‐intensity exercise. Fourteen trained male runners (V̇O2max${{\\dot{V}}_{{{\\mathrm{O}}}_2}{\\mathrm{max}}}$: 64 ± 5 mL/kg/min) randomly performed an incremental cardiopulmonary exercise test (CPET) to volitional exhaustion under four environmental conditions: normothermic (18°C) normoxia (FIO2${{F}_{{\\mathrm{I}}{{{\\mathrm{O}}}_2}}}$: 20.9%) and hypoxia (FIO2${{F}_{{\\mathrm{I}}{{{\\mathrm{O}}}_2}}}$: 13.5%), and cold (−20°C) normoxia and hypoxia. Ventilatory responses during exercise and lung function (LF), maximal inspiratory (MIP) and expiratory (MEP) pressure measurements before and after exercise were evaluated. Volume of air forcefully exhaled in 1 s (FEV1), FEV1/forced vital capacity (FVC), peak expiratory flow, forced expiratory flow during the mid (25–75%) portion of the FVC, and maximal expiratory flow at 50% of FVC were affected by cold exposure. No significant pre‐ to post‐exercise change in MIP and MEP was found, independent of environmental conditions. Greater LF impairments in cold‐normoxia and coldhypoxia were associated with the lowest peak ventilatory responses during exercise. Cold exposure was found to negatively impact peak ventilatory responses and post‐exercise LF, further highlighting a relationship between EIB presence and the blunted ventilatory response in the cold. Respiratory muscle strength remained unchanged after exercise regardless of the environmental condition, suggesting no detrimental effect of hypoxia on this parameter when intermittent short‐duration high‐intensity exercises are performed. Future studies should investigate the combined cold‐hypoxic effect on longer exercise durations at a sustained high intensity, accounting for differences between normobaric and hypobaric hypoxia exposures. What is the central question of this study? What are the independent and combined effects of cold and normobaric hypoxia on respiratory responses to high‐intensity exercise? What is the main finding and its importance? Cold exposure impaired lung function and peak ventilatory responses during high‐intensity exercise, with greater impairments observed under combined cold‐hypoxia condition. The findings highlight a link between exercise‐induced bronchoconstriction and reduced ventilatory capacity in cold environments. Respiratory muscle strength remained unaffected post‐exercise across all conditions, suggesting no detrimental impact of hypoxia during short‐duration high‐intensity tasks.

PurposeThis study investigated the effect of performing hypoxic exercise at the same heart rate (HR) or work rate (WR) as normoxic exercise on post-exercise autonomic and cardiovascular responses.MethodsThirteen men performed three interval-type exercise sessions (5 × 5-min; 1-min recovery): normoxic exercise at 80% of the WR at the first ventilatory threshold (N), hypoxic exercise (FiO2 = 14.2%) at the same WR as N (H-WR) and hypoxic exercise at the same HR as N (H-HR). Autonomic and cardiovascular assessments were conducted before and after exercise, both at rest and during active squat–stand manoeuvres (SS).ResultsCompared to N, H-WR elicited a higher HR response (≈ 83% vs ≈ 75%HRmax, p < 0.001) and H-HR a reduced exercise WR (− 21.1 ± 9.3%, p < 0.001). Cardiac parasympathetic indices were reduced 15 min after exercise and recovered within 60 min in N and H-HR, but not after H-WR (p < 0.05). H-WR altered cardiac baroreflex sensitivity (cBRS) both at rest and during SS (specifically in the control of blood pressure fall during standing phases) in the first 60 min after the exercise bout (p < 0.05). Post-exercise hypotension (PEH) did not occur in H-HR (p > 0.05) but lasted longer in H-WR than in N (p < 0.05).ConclusionsModerate HR-matched hypoxic exercise mimicked post-exercise autonomic responses of normoxic exercise without resulting in significant PEH. This may relate to the reduced WR and the limited associated mechanical/metabolic strain. Conversely, WR-matched hypoxic exercise impacted upon post-exercise autonomic and cardiovascular responses, delaying cardiac autonomic recovery, temporarily decreasing cBRS and evoking prolonged PEH.

Purpose To examine the effects of the world’s most challenging mountain ultra-marathon (Tor des Géants ® 2012) on the energy cost of three types of locomotion (cycling, level and uphill running) and running kinematics. Methods Before (pre-) and immediately after (post-) the competition, a group of ten male experienced ultra-marathon runners performed in random order three submaximal 4-min exercise trials: cycling at a power of 1.5 W kg −1 body mass; level running at 9 km h −1 and uphill running at 6 km h −1 at an inclination of +15 % on a motorized treadmill. Two video cameras recorded running mechanics at different sampling rates. Results Between pre- and post-, the uphill-running energy cost decreased by 13.8 % ( P  = 0.004); no change was noted in the energy cost of level running or cycling (NS). There was an increase in contact time (+10.3 %, P  = 0.019) and duty factor (+8.1 %, P  = 0.001) and a decrease in swing time (−6.4 %, P  = 0.008) in the uphill-running condition. Conclusion After this extreme mountain ultra-marathon, the subjects modified only their uphill-running patterns for a more economical step mechanics.

PurposeThis study investigated the effects of acute hypoxic exposure on post-exercise cardiac autonomic modulation following maximal cardiopulmonary exercise testing (CPET).MethodsThirteen healthy men performed CPET and recovery in normoxia (N) and normobaric hypoxia (H) (FiO2 = 13.4%, ≈ 3500 m). Post-exercise cardiac autonomic modulation was assessed during recovery (300 s) through the analysis of fast-phase and slow-phase heart rate recovery (HRR) and heart rate variability (HRV) indices.ResultsBoth short-term, T30 (mean difference (MD) 60.0 s, 95% CI 18.2–101.8, p = 0.009, ES 1.01), and long-term, HRRt (MD 21.7 s, 95% CI 4.1–39.3, p = 0.020, ES 0.64), time constants of HRR were higher in H. Fast-phase (30 and 60 s) and slow-phase (300 s) HRR indices were reduced in H either when expressed in bpm or in percentage of HRpeak (p < 0.05). Chronotropic reserve recovery was lower in H than in N at 30 s (MD − 3.77%, 95% CI − 7.06 to − 0.49, p = 0.028, ES − 0.80) and at 60 s (MD − 7.23%, 95% CI − 11.45 to − 3.01, p = 0.003, ES − 0.81), but not at 300 s (p = 0.436). Concurrently, Ln-RMSSD was reduced in H at 60 and 90 s (p < 0.01) but not at other time points during recovery (p > 0.05).ConclusionsAffected fast-phase, slow-phase HRR and HRV indices suggested delayed parasympathetic reactivation and sympathetic withdrawal after maximal exercise in hypoxia. However, a similar cardiac autonomic recovery was re-established within 5 min after exercise cessation. These findings have several implications in cardiac autonomic recovery interpretation and in HR assessment in response to high-intensity hypoxic exercise.

Purpose Uphill ski mountaineering performance appears to be related to metabolic cost of locomotion and skiers’ weight. The present study aimed to evaluate the effects of slight variations in equipment weight on metabolic and mechanical work (MW) of ski mountaineering, at race pace. Methods Thirteen male ski mountaineers were asked to ski on a treadmill at 25% slope and 80% of their maximal aerobic speed. They completed four 5-min bouts with additional weights of 0 kg (control), 0.2 kg, 0.4 kg, and 0.6 kg added to each ski boot in a blind mode and random order. Ski mountaineering energy cost (EC) was determined by gas exchange measurements, while MW was determined from the changes in the mechanical energy of body centre of mass (COM), body segments and equipment. Results EC and total MW were significantly (all p  < 0.001) and largely ( η 2  = 0.712 and η 2  = 0.704, respectively) increased for every 0.2 kg of mass added, by around 2% and 1%, respectively. The increase in the MW was related to a significant increase in the work needed to lift the weight against gravity and to the increased work done to move the segments of the lower body with respect to COM. Conclusion The present investigation shows that even small increments in racing gear weight are associated with an increase in ski mountaineering EC, possibly leading to a consequent decreased performance on uphill terrains.

Purpose Despite their increasing popularity, there are no studies analyzing the performance of ski-mountaineering vertical races. For the first time, this study examined a vertical competition, exploring the association between laboratory measures and uphill performance by means of multiple regression analysis. Methods Nine high-level ski-mountaineers (age 20.6 ± 3.0 years, V O 2max 69.3 ± 7.4 mL/min/kg) performed an anthropometric assessment and a laboratory ski-mountaineering graded exercise test (GXT) to evaluate V O 2max , gross efficiency (GE), ventilatory thresholds (VTs), blood lactate thresholds (LTs), as well as the power output associated with these indices. Race characteristics in terms of vertical gain, length, and mean gradient were, respectively, as follows: 460 m, 3 km, 15.3% for junior men and senior women; 600 m, 3.5 km, 17.1% for senior men. Results Average race time was 23:35 ± 01:25 (mm:ss). Mean power output exerted during the race was 3.40 ± 0.34 W/kg, equal to 79.0 ± 3.5% of maximal and 95.3 ± 5.2% of VT2 calculated in the GXT. The most performance-correlated variable was the V O 2 at VT2 (mL/min/kg) ( r  = 0.91, p  < 0.001), which accounted for the 80% of performance variation (adjusted R 2  = 0.80, p  = 0.001). When GE was included in the analysis, the regression model was significantly improved (adjusted R 2  = 0.90, p  = 0.031). Conclusions The study showed that the mean power output sustained during a vertical race is close to the power associated with VT2 and it is highly correlated with athletes’ physiological characteristics. Particularly, two variables, V O 2 at VT2 and GE, measurable with a specific GXT, accounted for the 90% of performance variation in a ski-mountaineering vertical race. Accordingly, training programs should focus on the maximal development of VT2 as well as on increasing GE by technical improvement.

Background Whole-body electromyostimulation (WB-EMS) has become increasingly popular under the promise to offer a time-saving and effective exercise protocols. Few studies estimating the training intervention intensity of WB-EMS are available in the literature. Aim The aim of this study was first to estimate the metabolic demand and muscle fatigue induced by a training session with WB-EMS, and second to compare them to a control intervention. Methods Ten young participants performed two training sessions: an experimental condition constituted by five exercises with superimposed WB-EMS and a control condition constituted by five body weight exercises. Both sessions lasted 15 min and were based on isometric intermittent contraction (6 of contraction interspersed by 4 s of rest). Muscle fatigue was assessed by determining the force decrease in the following tests: isometric mid-thigh pull; plyometric push-up; counter-movement jump. Oxygen consumption and energy expenditure were recorded by measuring respiratory gases exchange to quantify the metabolic demand of the exercises. Results The WB-EMS intervention required greater volume of oxygen consumed (WB-EMS 1584 ± 251 ml/min; control 1465 ± 216 ml/min, p  = 0.006) and energy expenditure (WB-EMS 470 ± 71 kcal/h; control 438 ± 61 kcal/h, p  = 0.013) than in control intervention. Overall, the WB-EMS training induced muscle fatigue (all PRE vs POST tests p  ≤ 0.02) whereas the body weight exercises did not (all p > 0.14). Conclusions These results indicate that WB-EMS intervention constituted a vigorous physical activity. The WB-EMS required also a greater metabolic demand and greater muscle fatigue than a traditional body weight circuit training. Thus, WB-EMS can be considered as an alternative training tool for physically active individuals.