Training load and intensity distribution for sprinting among world-class track cyclists.

BACKGROUND: Only few studies analyzed real training programs of sprinters while that should be a valuable step in the understanding of sprint training. The present study aimed at characterizing track cycling sprinter training by training load and intensity distribution. METHODS: Twenty-nine weeks of prechampionship training data were retrospectively analyzed for 6 world-class athletes. Training load was measured by the ratio of volume completed to maximal volume and categorized by five intensity zones (endurance: zones1-2; sprinting: zones3-5) and exercise type (on-bike or resistance). Intra-week (training monotony) and inter-week (acute-chronic workload ratio) variation was also studied. RESULTS: On-bike training represented 77.4±15.3% of total training load; resistance training, 22.6±15.2% (note high standard deviation). Total weekly training load significantly varied (P=0.0002) with high acute-chronic workload ratio (12.0±3.2 weeks >1.5 or <0.8), but low intra-week variations (training monotony, 1.81±0.20). Zone4 and zone5 made up 74.4±16.9% of total training load; zone1, 15.8±11%. Training load was seldom in zone2 (6.4±5.3%) or zone3 (3.3±4.2%). From the first to the second half of the period, zone3-4 training load decreased (39.3±3.3 to 27.4±1.7%; P=0.01), while zone5 increased (34.9±2.4 to 50±3.7%; P=0.002). CONCLUSIONS: In this reduced group of elite athletes, training appeared to mainly consist of on-bike exercises within the highest intensity zones. As demonstrated by monotony and acute-chronic workload ratio overloading and unloading are based on high variations over weeks, not days. Essentially, this study describes a polarized intensity distribution on the highest intensities which increased with world championships approach.

Acute effects of small changes in antero-posterior shoe-cleat position on physiological and biomechanical variables in road cycling.

The aim of this study was to investigate the effect of changes in cycling shoe-cleat position on pedalling biomechanics, physiological variables, and performance in road cycling. Twelve competitive road cyclists performed three pedalling trials with the cleat positioned at the first metatarsal head, 15-mm anterior and 15-mm posterior. Each trial included three sets of 5 min performed at 35%, 50%, and 65% of maximal aerobic power (MAP) followed by a 10-s sprint. Results showed no significant changes in physiological variables, pedalling kinetics, muscular activity of six lower limb muscles, sprint performance and perceived exertion. However, significant differences were found regarding joint kinematics: hip, knee, and ankle angles during both extension and flexion were reduced in the anterior cleat position. Therefore, this study suggests that cleat position does not affect sprint performance, physiological variables, pedalling kinetics, muscle activity, and perceived exertion regardless of the cycling intensity. However, joint kinematics, and particularly knee extension angle which could be related to the risk of overuse injuries, was affected by the shoe-cleat position.

Intra-cycle analysis of muscle vibration during cycling.

Cyclists are exposed for a long period to continuous vibrations. When a muscle is exposed to vibration, its efficiency decreases, the onset of fatigue occurs sooner, and the comfort of the cyclist is reduced. This study characterised the vastus lateralis (VL) soft tissue vibrations for different input frequencies and different pedalling phases. Ten cyclists were recruited to pedal at 55, 70, 85, and 100 rpm on a vibrating cycle ergometer that induced vibrations at frequencies ranging from 14.4 Hz (55 rpm) to 26.3 Hz (100 rpm). The VL vibration amplitude was quantified with a continuous wavelet transform and expressed as a function of the crank angle. The pedalling cycle was split into four phases (downstroke, backstroke, upstroke, and overstroke) to express the mean vibration amplitude and frequency of each phase. Statistical analysis depicted that VL vibration frequency increased with the pedalling cadence and that the VL was exposed to up to 50% more vibration amplitudes during the downstroke phase at a slow cadence. The increase in the pedal vibration frequency, a higher vibration transmission due to greater normal force on the pedal, and strong activation of the VL during the downstroke phase were discussed to explain these results.

Machine Learning Identifies Chronic Low Back Pain Patients from an Instrumented Trunk Bending and Return Test.

Nowadays, the better assessment of low back pain (LBP) is an important challenge, as it is the leading musculoskeletal condition worldwide in terms of years of disability. The objective of this study was to evaluate the relevance of various machine learning (ML) algorithms and Sample Entropy (SampEn), which assesses the complexity of motion variability in identifying the condition of low back pain. Twenty chronic low-back pain (CLBP) patients and 20 healthy non-LBP participants performed 1-min repetitive bending (flexion) and return (extension) trunk movements. Analysis was performed using the time series recorded by three inertial sensors attached to the participants. It was found that SampEn was significantly lower in CLBP patients, indicating a loss of movement complexity due to LBP. Gaussian Naive Bayes ML proved to be the best of the various tested algorithms, achieving 79% accuracy in identifying CLBP patients. Angular velocity of flexion movement was the most discriminative feature in the ML analysis. This study demonstrated that: supervised ML and a complexity assessment of trunk movement variability are useful in the identification of CLBP condition, and that simple kinematic indicators are sensitive to this condition. Therefore, ML could be progressively adopted by clinicians in the assessment of CLBP patients.

Sample Entropy as a Tool to Assess Lumbo-Pelvic Movements in a Clinical Test for Low-Back-Pain Patients.

Low back pain (LBP) obviously reduces the quality of life but is also the world's leading cause of years lived with disability. Alterations in motor response and changes in movement patterns are expected in LBP patients when compared to healthy people. Such changes in dynamics may be assessed by the nonlinear analysis of kinematical time series recorded from one patient's motion. Since sample entropy (SampEn) has emerged as a relevant index measuring the complexity of a given time series, we propose the development of a clinical test based on SampEn of a time series recorded by a wearable inertial measurement unit for repeated bending and returns (b and r) of the trunk. Twenty-three healthy participants were asked to perform, in random order, 50 repetitions of this movement by touching a stool and another 50 repetitions by touching a box on the floor. The angular amplitude of the b and r movement and the sample entropy of the three components of the angular velocity and acceleration were computed. We showed that the repetitive b and r "touch the stool" test could indeed be the basis of a clinical test for the evaluation of low-back-pain patients, with an optimal duration of 70 s, acceptable in daily clinical practice.

Caveats and Recommendations to Assess the Validity and Reliability of Cycling Power Meters: A Systematic Scoping Review.

A large number of power meters have become commercially available during the last decades to provide power output (PO) measurement. Some of these power meters were evaluated for validity in the literature. This study aimed to perform a review of the available literature on the validity of cycling power meters. PubMed, SPORTDiscus, and Google Scholar have been explored with PRISMA methodology. A total of 74 studies have been extracted for the reviewing process. Validity is a general quality of the measurement determined by the assessment of different metrological properties: Accuracy, sensitivity, repeatability, reproducibility, and robustness. Accuracy was most often studied from the metrological property (74 studies). Reproducibility was the second most studied (40 studies) property. Finally, repeatability, sensitivity, and robustness were considerably less studied with only 7, 5, and 5 studies, respectively. The SRM power meter is the most used as a gold standard in the studies. Moreover, the number of participants was very different among them, from 0 (when using a calibration rig) to 56 participants. The PO tested was up to 1700 W, whereas the pedalling cadence ranged between 40 and 180 rpm, including submaximal and maximal exercises. Other exercise conditions were tested, such as torque, position, temperature, and vibrations. This review provides some caveats and recommendations when testing the validity of a cycling power meter, including all of the metrological properties (accuracy, sensitivity, repeatability, reproducibility, and robustness) and some exercise conditions (PO range, sprint, pedalling cadence, torque, position, participant, temperature, vibration, and field test).

Comparison of two static methods of saddle height adjustment for cyclists of different morphologies.

Methods based on inseam length (IL) for saddle height adjustment in cycling are frequently employed. However, these methods were designed for medium-sized people. The aim of this study was to evaluate knee angle during pedalling by 2D video analysis and perceived comfort using a subjective scale under three saddle height conditions: (1) self-selected saddle height, (2) Genzling method (0.885 × IL) and (3) Hamley method (1.09 × IL minus crank arm length). Twenty-six cyclists of heterogeneous morphology were recruited. Three groups were determined based on IL: Short (IL < 0.8 m), Medium (0.8 m < IL< 0.88 m) and Long (IL > 0.88 m). The results showed that Medium and Long IL groups usually rode with saddle heights allowing knee angles consistent with those previously shown to prevent injuries (30°-40°). However, Short IL group, who were all children, self-selected a too low saddle height (knee angle was too large). Genzling and Hamley methods gave identical results for Medium IL group, permitting knee angles in the range of 30°-40°. However, both methods caused important differences between Short and Long IL groups. Hamley method was more suitable for short ILs, while Genzling method was more suitable for long ILs.

Physiological, biomechanical, and subjective effects of medio-lateral distance between the feet during pedalling for cyclists of different morphologies.

Improper medio-lateral distance between the feet in cycling can increase the risk of injuries and decrease performance due to hip/knee/ankle misalignment in the frontal plane. The objective of this study was to measure the impact of pedal spacing changes during pedalling on the biomechanical, physiological, and subjective variables of people with different morphologies. Twenty-two cyclists were divided into two groups according to their pelvis width (narrow and wide). They performed four submaximal pedalling tests with different pedal spindle lengths (+20 mm, +40 mm, and +60 mm compared to the pedal spindle lengths of standard road bikes). EMG activity, 3D joint kinematics of the lower limbs, comfort, and perceived exertion were measured during each test. Moreover, gas exchange data were collected to measure gross mechanical efficiency and cycling economy. No significant differences in muscular activity or joint kinematics were observed among the four experimental conditions. However, gross mechanical efficiency, cycling economy, and perceived comfort significantly improved while perceived exertion significantly reduced with the narrowest pedal spacing for the whole population, as well as for the narrow and wide pelvis groups. Therefore, the lowest medio-lateral distance between the feet seems more suitable for comfort and performance improvement, irrespective of the individual's morphology.

Adding Whole-Body Vibration to Preconditioning Squat Exercise Increases Cycling Sprint Performance.

Duc, S, Rønnestad, BR, and Bertucci, W. Adding whole-body vibration to preconditioning squat exercise increases cycling sprint performance. J Strength Cond Res 34(5): 1354-1361, 2020-This study investigated the effect of performing a preconditioning exercise with or without whole-body vibration (WBV) on a subsequent cycling sprint performance. Fourteen trained subjects performed 2 separate test sessions in randomized order. After a warm-up, the preconditioning exercise (body-loaded half-squats) was applied: 30 seconds of half-squats with WBV (40 Hz, 2 mm) or 30 seconds of half-squats without WBV with a 10-second all-out sprint performed after 1 minute. Surface electromyography (EMG) was measured from the vastus medialis, vastus lateralis, and gastrocnemius medialis during the sprints. Blood lactate level (BL), heart rate (HR), and rating of perceived exertion (RPE) were determined immediately after the 10-second sprint. Performing preconditioning exercise with WBV resulted in superior peak (1,693 ± 356 vs. 1,637 ± 349 W, p ≤ 0.05) and mean power output (1,121 ± 174 vs. 1,085 ± 175 W, p ≤ 0.05) compared with preconditioning exercise without WBV. Effect sizes showed a moderate and large practical effect of WBV vs. no WBV on peak and mean power output, respectively. No differences were observed between the conditions for BL, HR, and RPE after the sprints and in EMG activity during the sprints. In conclusion, it is plausible to suggest that body-loaded half-squats with WBV acutely induce higher power output levels. The practical application of the current study is that body-loaded squats with WBV can be incorporated into preparations for specific sprint training to improve the quality of the sprint training and also to improve sprint performance in relevant competitions.

Effect of Thigh-Compression Shorts on Muscle Activity and Soft-Tissue Vibration During Cycling.

Hintzy, F, Gregoire, N, Samozino, P, Chiementin, X, Bertucci, W, and Rossi, J. Effect of thigh-compression shorts on muscle activity and soft-tissue vibration during cycling. J Strength Cond Res 33(8): 2145-2152, 2019-This study examined the effects of different levels of thigh compression (0, 2, 6, and 15 mm Hg) in shorts on both vibration and muscle activity of the thigh during cycling with superimposed vibrations. Twelve healthy males performed a 18-minute rectangular cycling test per shorts condition (randomized cross-over design) on a specifically designed vibrating cycloergometer. Each test was composed of 2 intensity levels (moderate then high) and 3 vibration frequencies of 18.3, 22.4, and 26.3 Hz, corresponding to cadences of 70, 85, and 100 rpm, respectively. Muscle vibrations were measured with 2 triaxial accelerometers located before and on the lower-body compression garment, to quantify, respectively, the input and output vibrations, and vastus lateralis muscle activity was measured using surface electromyography. Both vibration and electromyography signals were measured throughout the tests and quantified using root-mean-square analyses. The study showed that the use of a thigh-compression shorts at 6-15 mm Hg significantly reduced both the vibration transmissibility to the thigh and the muscle activity, with higher effect size at higher superimposed vibrations. The thigh-compression shorts garment therefore seems to be 1 way to dampen vibrations transmitted to the cyclists and then to reduce the negative consequences of these vibrations on muscles.

A retrospective international study on factors associated with injury, discomfort and pain perception among cyclists.

Although cycling has been associated with overuse/fatigue and acute injuries, there is lack of information regarding associated risk factors and prevention factors. The objective of the study was to determine the factors associated with injury, and perceptions of discomfort and pain in cyclists. A total of 739 cyclists completed an online questionnaire between February and October 2016. The questionnaire acquired information on participant demographics, characteristics related to cycling profile and fitness training, bike components and cycling posture, self-reported perceptions of comfort and pain, and injuries sustained in the last 12 months. Logistic regression models estimated odds ratios (OR) and 95% confidence intervals (95%CI) that examined factors associated with reporting overuse/fatigue injury, acute injury, body discomfort, saddle discomfort, and pain while cycling. Odds of reporting an overuse/fatigue injury increased when the cyclists complemented training with running (OR = 1.74; 95%CI = 1.03-2.91) or swimming (OR = 2.17; 95%CI = 1.19-3.88), and with reported pain while cycling (OR = 1.17; 95%CI = 1.05-3.69) and not cycling (OR = 1.76; 95%CI = 1.07-2.90). Odds of reporting an acute injury increased when biking to work (OR = 1.79; 95%CI = 1.07-2.86), and decreased with increased average cycling speed (1-km/h decrease OR = 0.93; 95%CI = 0.88-0.97), and compared to low-end bike, with the use of mid-range (OR = 0.25; 95%CI = 0.09-0.72) and high-end bike (OR = 0.34; 95%CI = 0.13-0.96). Although body discomfort was only associated with saddle discomfort and the presence of pain during cycling, saddle discomfort was also associated with biking to work (OR = 0.46; 95%CI = 0.22-0.88). Finally, pain perception was associated with a number of factors such as ride to work, core training, cycling experience, saddle discomfort, pain while not cycling. Numerous factors are associated with injury, and perceptions of discomfort and pain in cyclists. Such factors should be considered when developing training routines, bicycle maintenance best practices, and injury prevention programs.

Comparison of static and dynamic methods based on knee kinematics to determine optimal saddle height in cycling.

PURPOSE: Bike-fitting methods based on knee kinematics have been proposed to determine optimal saddle height. The Holmes method recommends that knee angle be between 25° and 35° when the pedal is at bottom dead centre in static. Other authors advocate knee angle of 30-40° during maximum knee extension while pedalling. Although knee angle would be 5-10° greater at bottom dead centre during pedalling, no study has reported reference values in this condition. The purpose of this study was to compare these three methodologies on knee, hip, and ankle angles and to develop new dynamic reference range at bottom dead centre. METHODS: Twenty-six cyclists volunteered for this experiment and performed a pedalling test on their personal road or mountain bike. Knee, hip, and ankle angles were assessed by two-dimensional video analysis. RESULTS: Dynamic knee angle was 8° significantly greater than static knee angle when the pedal was at bottom dead centre. Moreover, dynamic knee angle with the pedal at bottom dead centre was 3° significantly greater than dynamic knee angle during maximum knee extension. The chosen methodology also significantly impacted hip and ankle angles under most conditions. CONCLUSIONS: The results allow us to suggest a new range of 33-43° when the pedal is at bottom dead centre during pedalling. Thus, this study defines clearly the different ranges to determine optimal saddle height in cycling according to the condition of measurement. These findings are important for researchers and bike-fitting professionals to avoid saddle height adjustment errors that can affect cyclists' health and performance.

Strategies for improving the pedaling technique.

INTRODUCTION: Pedaling technique which can be defined as the way the cyclists pedal, has been mostly studied in lab conditions from pedal force kinetic, joints kinematic, and/or muscular activity patterns because it is considered as a main factor for gross efficiency (GE). Although this method is much controversial, its quality has extensively been evaluated from the index of pedal force effectiveness (IFE), i.e. the ratio between the effective to the total pedal force. Over the last thirty years, preferred pedaling technique has been compared between the experienced cyclists and non-cyclists and also often been manipulated by instructing these subjects to improve their effective force production during the downstroke phase ("pushing"), the upstroke phase ("pulling-up") or around top and bottom dead centers ("circling"). EVIDENCE ACQUISITION: It has been shown that PREF pedaling technique is much repeatable across crank cycles in experienced cyclists than in novice cyclists. PULL involves a significant increase of IFE compared to PREF, mainly attributed to the increase of the muscular work of hip (RF) and knee flexors muscles (BF) during the upstroke. This improvement is larger in non-cyclists than in experienced cyclists but it can be optimized in the latter after a short-term training (2-4 weeks) with pedal force feedback or uncoupled cranks. EVIDENCE SYNTHESIS: Despite that PULL enhances a lower muscular recruitment of contralateral knee extensors, GE and cycling performance variables are not significantly increased, probably due to the reversal effect of training with normal cranks and the highly robust pedaling technique of experienced cyclists. The question arises, as to whether or not, changes in pedaling technique can improve cycling efficiency if enough time is given for cyclists to adapt to a new pedaling technique. CONCLUSIONS: Further studies should investigate the pedaling techniques in more "ecological" conditions, as there is not probably one but several pedaling techniques that could optimize cycling efficiency according to the pedaling conditions (time-trial, uphill, road, off-road and track cycling), and should also focus on the potential effects of long-term training of PULL pedaling technique on cycling efficiency and cycling performance.

The association of bike fitting with injury, comfort, and pain during cycling: An international retrospective survey.

Although bike fitting is recommended to help reduce injury risk, little empirical evidence exists to indicate an association between bike fitting and injury incidence. The aim of the study was to determine the effect of bike fitting on self-reported injury, comfort, and pain while cycling from a worldwide survey of cyclists. A total of 849 cyclists completed an online questionnaire between February and October 2016. Questionnaire collected data on respondent demographics, cycling profile, bike fitting, comfort and pain while cycling, and injury history. The main predictor variable was bike fitting (yes, by the respondent, i.e. user bike fitting; yes, by a professional service; or no). Covariates included demographic and cycling profile characteristics. Logistic regression models estimated the odds of injury within the last 12 months, reporting a comfortable body posture while cycling, and not reporting pain while cycling. Odds ratios (OR) with 95% confidence intervals (CI) were reported. User bike fitting was associated with increased odds of reporting a comfortable posture (OR = 2.28, 95%CI: 1.06, 4.68). User (OR = 2.35; 95%CI: 1.48, 3.84) and professional bike fitting (OR = 2.35; 95%CI: 1.42, 3.98) were both associated with increased odds of not reporting pain while cycling. No associations were found between bike fitting and injury within the last 12 months. In conclusion, we found an association between bike fitting and reported comfort and pain while cycling. We recommend integrating bike fitting into cycling maintenance. However, further studies with longer follow-up are necessary to determine the presence of an association between bike fitting and injury.

The categorization of amateur cyclists as research participants: findings from an observational study.

Sampling bias is an issue for research involving cyclists. The heterogeneity of cyclist populations, on the basis of skill level and riding purpose, can generate incorrect inferences about one specific segment of the population of interest. In addition, a more accurate categorization would be helpful when physiological parameters are not available. This study proposes using self-reported data to categorize amateur cyclist types by varying skill levels and riding purposes, therefore improving sample selection in experimental studies. A total of 986 cyclists completed an online questionnaire between February and October 2016. Two-step cluster analyses were performed to generate distinct groups, and dependent variables of these groups were compared (demographics and characteristics of cycling practice). The cluster analysis relied on 4 descriptors (cycling weekly volume, average cycling speed, riding purpose, and cycling discipline) and yielded five distinct groups: competitive road, recreational road, competitive mountain bike (MTB), recreational MTB and competitive triathlon. Among these groups, averages and distributions for age, height, body mass, body mass index, training volume and intensity, and years of experience varied. This categorization can potentially help researchers recruit specific groups of cyclists based upon self-reported data and therefore better align the sample characteristic with the research aims.

Analysis of muscular activity and dynamic response of the lower limb adding vibration to cycling.

Vibration in cycling has been proved to have undesirable effects over health, comfort and performance of the rider. In this study, 15 participants performed eight 6-min sub-maximal pedalling exercises at a constant power output (150W) and pedalling cadence (80 RPM) being exposed to vibration at different frequencies (20, 30, 40, 50, 60, 70 Hz) or without vibration. Oxygen uptake (VO2), heart rate (HR), surface EMG activity of seven lower limb muscles (GMax, RF, BF, VM, GAS, SOL and TA) and 3-dimentional accelerations at ankle, knee and hip were measured during the exercises. To analyse the dynamic response, the influence of the pedalling movement was taken into account. The results show that there was not significant influence of vibrations on HR and VO2 during this pedalling exercise. However, muscular activity presents a significant increase with the presence of vibration that is influenced by the frequency, but this increase was very low (< 1%). Also, the dynamic response shows an influence of the frequency as well as an influence of the different parts of the pedalling cycle. Those results help to explain the effects of vibration on the human body and the influence of the rider/bike interaction in those effects.

Validity, Sensitivity, Reproducibility, and Robustness of the PowerTap, Stages, and Garmin Vector Power Meters in Comparison With the SRM Device.

A large number of power meters have been produced on the market for nearly 20 y according to user requirements. PURPOSE: To determine the validity, sensitivity, reproducibility, and robustness of the PowerTap (PWT), Stages (STG), and Garmin Vector (VCT) power meters in comparison with the SRM device. METHODS: A national-level male competitive cyclist completed 3 laboratory cycling tests: a submaximal incremental test, a submaximal 30-min continuous test, and a sprint test. Two additional tests were performed, the first on vibration exposures in the laboratory and the second in the field. RESULTS: The VCT provided a significantly lower 5-s power output (PO) during the sprint test with a low gear ratio than the SRM did (-36.9%). The STG PO was significantly lower than the SRM PO in the heavy-exercise-intensity zone (zone 2, -5.1%) and the low part of the severe-intensity zone (zone 3, -4.9%). The VCT PO was significantly lower than the SRM PO only in zone 2 (-4.5%). The STG PO was significantly lower in standing position than in the seated position (-4.4%). The reproducibility of the PWT, STG, and VCT was similar to that of the SRM system. The STG and VCT PO were significantly decreased from a vibration frequency of 48 Hz and 52 Hz, respectively. CONCLUSIONS: The PWT, STG, and VCT systems appear to be reproducible, but the validity, sensitivity, and robustness of the STG and VCT systems should be treated with some caution according to the conditions of measurement.

Transmission of whole body vibration to the lower body in static and dynamic half-squat exercises.

Whole body vibration (WBV) is used as a training method but its physical risk is not yet clear. Hence, the aim of this study is to assess the exposure to WBV by a measure of acceleration at the lower limb under dynamic and static postural conditions. The hypothesis of this paper is that this assessment is influenced by the frequency, position, and movement of the body. Fifteen healthy males are exposed to vertical sinusoidal vibration at different frequencies (20-60 Hz), while adopting three different static postures (knee extension angle: 180°, 120° and 90°) or performing a dynamic half-squat exercise. Accelerations at input source and at three joints of the lower limb (ankle, knee, and hip) are measured using skin-mounted accelerometers. Acceleration values (g) in static conditions show a decrease in the vibrational dose when it is measured at a more proximal location in the lower extremity. The results of the performed statistical test show statistically significant differences (p < 0.05) in the transmissibility values caused by the frequency, the position, and to the presence of the movement and its direction at the different conditions. The results confirm the initial hypothesis and justify the importance of a vibration assessment in dynamic conditions.

Acute Effects of Aerobic Exercise on Feelings of Energy in Relation to Age and Sex.

A crossover experiment was performed to determine whether age and sex, or their interaction, affect the impact of acute aerobic exercise on vigor-activity (VA). We also tested whether changes in VA mediated exercise effects on performance on various cognitive tasks. Sixty-eight physically inactive volunteers participated in exercise and TV-watching control conditions. They completed the VA subscale of the Profile of Mood States immediately before and 2 min after the intervention in each condition. They also performed the Trail Making Test 3 min after the intervention in each condition. Statistical analyses produced a condition . age . sex interaction characterized by a higher mean VA gain value in the exercise condition (compared with the VA gain value in the TV-watching condition) for young female participants only. In addition, the mediational analyses revealed that changes in VA fully mediated the effects of exercise on TMT-Part A performance.

Do Changes in Tympanic Temperature Predict Changes in Affective Valence During High-Intensity Exercise?

PURPOSE: Increased core (brain or body) temperature that accompanies exercise has been posited to play an influential role in affective responses to exercise. However, findings in support of this hypothesis have been equivocal, and most of the performed studies have been done in relation to anxiety. The aim of the present study was to investigate the effects of tympanic temperature on basic affect (i.e., pleasure-displeasure) in the course of a high-intensity exercise session. METHOD: One hundred seventy students performed a 10-min cycling exercise at an intensity of 80% to 85% of maximal heart rate. Heart rate, tympanic temperature, and self-reported pleasure (using the Feeling Scale [FS]) were measured twice during exercise at the end of the first minute (Min 1:00) and beginning of the last minute (Min 9:00). RESULTS: Small increases in tympanic temperature were noted from Min 1:00 to Min 9:00 (mean change value = +0.2°C). Meanwhile, the FS scores changed in the opposite direction (mean change value = - 0.2 units). However, changes in temperature only poorly predicted changes in pleasure-displeasure (R(2) = .05 for the linear regression, R(2) = .08 for the curvilinear regression). CONCLUSIONS: Slight elevated tympanic temperature occurred during the 10-min cycling exercise, but it had a negligible effect on changes in pleasure ratings. The possibility that tympanic temperature is not a valid indicator of core temperature during exercise is discussed.