The psychophysiological regulation of pacing behaviour and performance during prolonged endurance exercise

Current models of exercise regulation almost solely rely on the Gestalt phenomenon of perceived exertion. This limits a more comprehensive understanding of how causeeffect relationships come to be and how perception-action coupling determines pacing behaviour and performance fatigability. A three-dimensional framework of centrally regulated and goal-directed exercise behaviour is proposed, which differentiates between sensory-discriminatory, affectivemotivational, and cognitive-evaluative processes hypothesised to underpin perceived fatigability. In short: (A) perceived physical strain and perceived mental strain are primary regulators of pacing behaviour necessary to align planned behaviour with current physiological state, (B) core affect plays a primary and mediatory role in performance regulation, and (C) the mindset- shift associated with an action crisis plays a primary role in volitional self-regulatory control and decision-making. In study one, 23 cyclists of distinct performance levels engaged in 70-km individual and head-to-head competition time trials against a performance matched opponent. Sensory constructs were primarily associated with regulation of pacing behaviour. Affective and cognitive constructs acted as context-dependent modifiers and were primarily associated with regulation of performance. A five-step structural equation modelling procedure was applied to assess the extent to which the observed data fit the hypothesised cause–effect relationships under the constraint of psychological duress: valence deterioration was found to mediate the relationship between falling-behind and action crisis; which in turn predicted increased non-adaptive endocrinological distress response; which in turn predicted performance decrement. In study two, 22 highly-trained runners completed two self-paced 20-km treadmill time trials in a tapered condition and with locomotor muscle fatigue and exercise-induced muscle damage. The latter was associated with medium increases in markers of physiological distress and large alterations in perceived physical strain, affective valence, and cognitive mindset. This indicates heuristic and rational antecedents in the goal-disengagement process. Structural equation modelling confirmed the hypothesised dual-pathway model under the constraint of physical duress: haematological indicators of EIMD predicted (1) amplified physiological strain and non-adaptive endocrinological distress response and (2) increase in perceived physical strain, which mediated and predicted decrease in valence; which in turn predicted an increase in action crisis; and both physiological and perceptual effects predicted performance fatigability. The proposed framework has the potential to enrich theory development in centrally regulated and goal-directed exercise behaviour by providing novel insights into and more complete account of the dynamic and complex processes in strain-perceptionthinking-action coupling during prolonged endurance exercise

Does Higher Intensity Increase the Rate of Responders to Endurance Training When Total Energy Expenditure Remains Constant? : A Randomized Controlled Trial

Background Standardized training prescriptions often result in large variation in training response with a substantial number of individuals that show little or no response at all. The present study examined whether the response in markers of cardiorespiratory ftness (CRF) to moderate intensity endurance training can be elevated by an increase in training intensity. Methods Thirty-one healthy, untrained participants (46±8 years, BMI 25.4±3.3 kg m−2 and V˙O2max 34±4 mL min−1 kg−1 ) trained for 10 weeks with moderate intensity (3 day week−1 for 50 min per session at 55% HRreserve). Hereafter, the allocation into two groups was performed by stratifed randomization for age, gender and VO2max response. CON (continuous moderate intensity) trained for another 16 weeks at moderate intensity, INC (increased intensity) trained energy-equivalent for 8 weeks at 70% HRreserve and then performed high-intensity interval training (4×4) for another 8 weeks. Responders were identifed as participants with VO2max increase above the technical measurement error. Results There was a signifcant diference in V˙O2max response between INC (3.4±2.7 mL kg−1 min−1 ) and CON (0.4±2.9 mL kg−1 min−1 ) after 26 weeks of training (P=0.020). After 10 weeks of moderate training, in total 16 of 31 participants were classifed as VO2max responders (52%). After another 16 weeks continuous moderate intensity training, no further increase of responders was observed in CON. In contrast, the energy equivalent training with increasing training intensity in INC signifcantly (P=0.031) increased the number of responders to 13 of 15 (87%). The energy equivalent higher training intensities increased the rate of responders more efectively than continued moderate training intensities (P=0.012). Conclusion High-intensity interval training increases the rate of response in VO2max to endurance training even when the total energy expenditure is held constant. Maintaining moderate endurance training intensities might not be the best choice to optimize training gains. Trial Registration German Clinical Trials Register, DRKS00031445, Registered 08 March 2023—Retrospectively registered, https://www.drks.de/DRKS0003144

Effects on cardiorespiratory fitness of moderate-intensity training vs. energy-matched training with increasing intensity

Introduction: The present study investigated the role of training intensity in the dose–response relationship between endurance training and cardiorespiratory fitness (CRF). The hypothesis was that beginners would benefit from an increase in training intensity after an initial training phase, even if the energy expenditure was not altered. For this purpose, 26 weeks of continuous moderate training (control group, CON) was compared to training with gradually increasing intensity (intervention group, INC) but constant energy expenditure. Methods: Thirty-one healthy, untrained subjects (13 men, 18 women; 46 ± 8 years; body mass index 25.4 ± 3.3 kg m−2 ; maximum oxygen uptake, VO2max 34 ± 4 ml min−1 kg−1 ) trained for 10 weeks with moderate intensity [3 days/ week for 50 min/session at 55% heart rate reserve (HRreserve)] before allocation to one of two groups. A minimization technique was used to ensure homogeneous groups. While group CON continued with moderate intensity for 16 weeks, the INC group trained at 70% HRreserve for 8 weeks and thereafter participated in a 4 × 4 training program (high-intensity interval training, HIIT) for 8 weeks. Constant energy expenditure was ensured by indirect calorimetry and corresponding adjustment of the training volume. Treadmill tests were performed at baseline and after 10, 18, and 26 weeks. Results: The INC group showed improved VO2max (3.4 ± 2.7 ml kg−1 min−1 ) to a significantly greater degree than the CON group (0.4 ± 2.9 ml kg−1 min−1 ) (P = 0.020). In addition, the INC group exhibited improved Vmax (1.7 ± 0.7 km h−1 ) to a significantly greater degree than the CON group (1.0 ± 0.5 km h−1 ) (P = 0.001). The reduction of resting HR was significantly larger in the INC group (7 ± 4 bpm) than in the CON group (2 ± 6 bpm) (P = 0.001). The mean heart rate in the submaximal exercise test was reduced significantly in the CON group (5 ± 6 bpm; P = 0.007) and in the INC group (8 ± 7 bpm; P = 0.001), without a significant interaction between group and time point

Modelling perception-action coupling in the phenomenological experience of “hitting the wall” during long-distance running with exercise-induced muscle damage in highly trained runners

Background “Hitting the wall” (HTW) can be understood as a psychophysiological stress process characterised by (A) discrete and poignant onset, (B) dynamic interplay between physiological, affective, motivational, cognitive, and behavioural systems, and (C) unintended alteration of pace and performance. A preceding companion article investigated the psychophysiological responses to 20-km self-paced treadmill time trials after producing exercise-induced muscle damage (EIMD) via a standardised muscle-lengthening contraction protocol. Methods A 5-step procedure was applied determining the extent to which the observed data fit the hypothesised cause-effect relationships. Running with EIMD negatively impacts performance fatigability via (A) amplified physiological responses and a non-adaptive distress response and (B) deterioration in perceived fatigability: increase in perceived physical strain precedes decrease in valence, which in turn precedes increase in action crisis, eventually dissolving the initially aspired performance goal. Results First, haematological indicators of EIMD predicted increased blood cortisol concentration, which in turn predicted increased performance fatigability. Second, perceived physical strain explained 44% of the relationship between haematological indicators of EIMD and valence, which in turn predicted increased action crisis, which in turn predicted increased performance fatigability. The observed data fitted the hypothesised dual-pathway model well with good model-fit indices throughout. Conclusions The hypothesised interrelationships between physiological strain, perception, and heuristic and deliberative decision-making processes in self-regulated and goal-directed exercise behaviour were applied, tested, and confirmed: amplified physiological strain and non-adaptive distress response as well as strain-perception-thinking-action coupling impact performance fatigability. The findings provide novel insights into the psychophysiological processes that underpin the phenomenological experience of HTW and alteration in pacing behaviour and performance

Effects of face masks on performance and cardiorespiratory response in well-trained athletes

Background During the COVID-19 pandemic, compulsory masks became an integral part of outdoor sports such as jogging in crowded areas (e.g. city parks) as well as indoor sports in gyms and sports centers. This study, therefore, aimed to investigate the effects of medical face masks on performance and cardiorespiratory parameters in athletes. Methods In a randomized, cross-over design, 16 well-trained athletes (age 27 ± 7 years, peak oxygen consumption 56.2 ± 5.6 ml kg−1 min−1, maximum performance 5.1 ± 0.5 Watt kg−1) underwent three stepwise incremental exercise tests to exhaustion without mask (NM), with surgical mask (SM) and FFP2 mask (FFP2). Cardiorespiratory and metabolic responses were monitored by spiroergometry and blood lactate (BLa) testing throughout the tests. Results There was a large effect of masks on performance with a significant reduction of maximum performance with SM (355 ± 41 Watt) and FFP2 (364 ± 43 Watt) compared to NM (377 ± 40 Watt), respectively (p < 0.001; ηp2 = 0.50). A large interaction effect with a reduction of both oxygen consumption (p < 0.001; ηp2 = 0.34) and minute ventilation (p < 0.001; ηp2 = 0.39) was observed. At the termination of the test with SM 11 of 16 subjects reported acute dyspnea from the suction of the wet and deformed mask. No difference in performance was observed at the individual anaerobic threshold (p = 0.90). Conclusion Both SM and to a lesser extent FFP2 were associated with reduced maximum performance, minute ventilation, and oxygen consumption. For strenuous anaerobic exercise, an FFP2 mask may be preferred over an SM

Längsschnittstudie zur Eignung der Herzfrequenzvariabilität in der Trainingsteuerung

$\bf Problem:$ Die hohen Belastungsumfänge und -intensitäten in den Ausdauersportarten führen immer öfter zu Verletzungen, Infekten und Übertrainingszuständen. Die Herzfrequenzvariabilitätsmessung könnte über eine Bewertung der vegetativen Balance des autonomen Nervensystems zur Optimierung der Trainingssteuerung beitragen. $\bf Methode:$ 6 Triathleten zeichneten über 6 Monate morgendlich Herzfrequenz, tonische und reflektorische HRV-Parameter sowie Trainingsinhalte auf. $\bf Ergebnisse:$ Es fanden sich signifikante Zusammenhänge zwischen den Untersuchungsparametern und Einflussvariablen. Ein fester zeitlicher Zusammenhang oder allgemeine Regeln konnten sich nicht ableiten lassen. Anpassungsreaktionen der HRV in Abhängigkeit von Trainingsperioden konnten nachgewiesen werden. $\bf Diskussion:$ Die gefundenen Unterschiede waren qualitativ und quantitativ nur gering ausgeprägt und sind bei insgesamt sehr großer inter- und intraindividueller Variation zur Trainingssteuerung nicht brauchbar

Additional file 1: of The Psychophysiological Regulation of Pacing Behaviour and Performance Fatigability During Long-Distance Running with Locomotor Muscle Fatigue and Exercise-Induced Muscle Damage in Highly Trained Runners

Supplementary material containing findings in (1) deterioration in jump-height during the drop-jump protocol and the development of DOMS in the 84-h recovery period after experimental trials, (2) distributions of individual differences in knee extensor power output, time trial time, and time trial splits, (3) statistical details of two-way repeated measures ANOVA’s (trial × time) including follow-up tests and non-parametric ANOVA’s in perceptive variables, and (4) results of three-way mixed repeated measures ANOVA’s (trial × time × sex). (PDF 317 kb

The association of end-spurt behaviour with seasonal best time in long-distance freestyle pool swimming

To analyse the association of seasonal best time, distance and different performance levels with end-spurt behaviour in one swimming season. Race results in 800 and 1500 m pool freestyle swimming in the season 2018/2019 including 14,930 races and 2650 swimmers were obtained. The end-spurt for each race was determined by means of an End-Spurt Indicator (ESI). Subsequently, ESI was used as a dependent variable and influences were analysed using a linear mixed model with fixed effects for seasonal best time, distance, and performance level amongst others. In the 800 and 1500 m races swimmers showed a mean ESI of 2.08 (95% CI: 2.02–2.13) and 3.68 (95% CI: 3.59–3.76), respectively. There was a significant association between seasonal best time and ESI, with a better seasonal best time showing a greater ESI (F = 70.5, P < .001, f2 = 0.04). A significant effect on greater ESI was also observed for longer distance (F = 1067.5, P < .001, f2 = 0.06) and higher performance level (F = 91.1, P < .001, f2 = 0.02). Elite swimmers had a mean ESI of 5.47 (95% CI: 4.91–6.03), sub-elite swimmers of 3.74 (95% CI: 3.53–3.95) and competitive swimmers of 2.41 (95% CI: 2.37–2.46). A more pronounced end-spurt is associated with seasonal best time in long-distance pool swimming, higher performance level of the swimmer and longer race distance

Additional file 1: of Modelling perception-action coupling in the phenomenological experience of “hitting the wall” during long-distance running with exercise-induced muscle damage in highly trained runners

Supplementary material contains graphical and tabular information on the 5-step structural equation modelling procedure using differential responses in flow state instead of action crisis: (1) trial-related differences in main study variables in response to running with exercise-induced muscle damage, (2) zero-order correlations between trial-related differences in area under the curve of main study variables, (3) multiple hierarchical regression analyses of control variables, direct predictor variables, and main study outcome variables, and (4) structural equation model of physiological and percpetual effects on performance fatigability. (PDF 452 kb

Effects on cardiorespiratory fitness of moderate-intensity training vs. energy-matched training with increasing intensity

Introduction: The present study investigated the role of training intensity in the dose–response relationship between endurance training and cardiorespiratory fitness (CRF). The hypothesis was that beginners would benefit from an increase in training intensity after an initial training phase, even if the energy expenditure was not altered. For this purpose, 26 weeks of continuous moderate training (control group, CON) was compared to training with gradually increasing intensity (intervention group, INC) but constant energy expenditure. Methods: Thirty-one healthy, untrained subjects (13 men, 18 women; 46±8 years; body mass index 25.4 ± 3.3 kg m−2; maximum oxygen uptake, VO2max −1 −1 34 ± 4 ml min kg ) trained for 10 weeks with moderate intensity [3 days/week for 50 min/session at 55% heart rate reserve (HRreserve)] before allocation to one of two groups. A minimization technique was used to ensure homogeneous groups. While group CON continued with moderate intensity for 16 weeks, the INC group trained at 70% HRreserve for 8weeks and thereafter participated in a 4 × 4 training program (high-intensity interval training, HIIT) for 8 weeks. Constant energy expenditure was ensured by indirect calorimetry and corresponding adjustment of the training volume. Treadmill tests were performed at baseline and after 10, 18, and 26 weeks. Results: The INC group showed improved VO2max (3.4 ± 2.7 ml kg−1 min−1) to a significantly greater degree than the CON group (0.4 ± 2.9 ml kg−1 min−1) (P = 0.020). In addition, the INC group exhibited improved Vmax (1.7 ± 0.7 km h−1) to a significantly greater degree than the CON group (1.0 ± 0.5 km h−1) (P = 0.001). The reduction of resting HR was significantly larger in the INC group (7±4bpm) than in the CON group (2±6bpm) (P=0.001). The mean heart rate in the submaximal exercise test was reduced significantly in the CON group (5±6bpm; P=0.007) and in the INC group (8±7bpm; P=0.001), without a significant interaction between group and time point