Rating Of Perceived Exertion Scores Research Articles

Sex- and age-related differences in the rating of perceived exertion after high-intensity rowing exercise during childhood and adolescence.

The present study aimed to evaluate the effects of age and sex on the rating of perceived exertion (RPE) during high-intensity exercise and determine whether mechanical and physiological parameters could be predictors of RPE during childhood and adolescence. Forty-three boys and 36 girls performed a 60-s all-out test on a rowing ergometer and were categorized by age group (10.0-11.9; 12.0-13.9; 14.0-15.9; 16.0-17.9 years) and sex. Ratings of perceived exertion were assessed using the 6-20 RPE and CR-10 scales and analyzed with respect to mechanical work rate (Wtot ), post-exercise peak blood lactate concentration ([La]peak ), and peak minute ventilation (V̇Epeak ). Multilevel regression modeling revealed a significant influence of Wtot , [La]peak and V̇Epeak on 6-20 RPE and CR-10 scores (r2 =.34 and .36, p < .001, respectively). However, while boys perceived high-intensity exercise as being subjectively more difficult than girls at all ages (p < .05) except 12.0-13.9 years, significant higher mechanical work rate and greater associated metabolic responses in boys than girls were only found from the age of 14 years (Wtot and V̇Epeak ) or 16 years ([La]peak ), suggesting that the association between RPE and mechanical/physiological parameters could not be held before the age of 12 years. To conclude, RPE increased with increasing age, with boys exhibiting higher scores than girls at all ages except 12.0-13.9 years. This finding is probably explained by the higher Wtot and greater concomitant metabolic responses in boys at the time of puberty. However, other factors should be considered at least in children before the age of 12 years.

Is moderate-intensity interval training more tolerable than high-intensity interval training in adults with obesity?

Interval training (IT) has been shown to be a time-effective alternative to traditional training programmes in the management of obesity. Nevertheless, studies comparing the effects of different IT intensities on inflammation, muscle and liver damage, and perceptual responses in people with obesity are relatively scarce. This study aimed to compare the acute effects of two different IT protocols matched by the mean load and duration on biochemical and perceptual responses in sedentary adults with obesity. Twenty-two volunteers (age = 33.40 ± 10.01 years, BMI = 38.29 ± 7.09 kg/m²) were randomized to perform two conditions: moderate-intensity IT (MIIT) 5 × 3 min (70% of peak power output (PPO))/2 min (45%PPO) and high-intensity IT (HIIT) 8 × 1 min (90%PPO)/2 min (45%PPO). Blood samples were drawn before and after exercise for biochemical and haematological measurements. Rating of perceived exertion (RPE) was assessed during and after exercise. Perceptual pain was evaluated before, throughout and after exercise. C-reactive protein, white blood cells and neutrophils increased only after HIIT (p < 0.001, for all). Aspartate aminotransferase, alanine aminotransferase, creatine kinase and lactate dehydrogenase increased in both HIIT and MIIT (p < 0.001, for all), without any difference between sessions. HIIT induced a greater increase of blood lactate compared to MIIT (p < 0.05). Pain and RPE scores were higher during HIIT vs. MIIT (p < 0.001 and p < 0.01, respectively). MIIT induced fewer immune system perturbations and less muscle pain and was perceived as more tolerable compared to HIIT session. Therefore, MIIT could be used as a first step to promote body adaptations before starting a HIIT programme in sedentary people with obesity.

The effect of time of day and high intensity exercise on cognitive performances of elite adolescent karate athletes

ABSTRACT To explore the effect of time of day (TOD) on several components of cognitive performance prior and post to a physically exhaustive task in a sample of adolescent elite athletes. In a counterbalanced and randomized order, fourteen highly trained male karate athletes (17 ± 0.96 years; 1.75 ± 0.07 m; 68.0 ± 9.50 kg; BMI 22.15 ± 0.54 kg.m−2) completed two test sessions at 09h00 and 16h00. Cognitive performance was evaluated before and after the karate specific test (KST). During each session, participants completed the profile of mood state (POMS), simple (SRT) and choice (CRT) reaction times, comparison test (COMT), mental rotation test (MRT), egocentric distance estimation (DE), and the rating of perceived exertion (RPE). KST was not TOD dependent (p > .05, d = 0.33). RPE scores were higher in the afternoon compared to the morning (p < .05, d = 0.68). Before the KST, SRT (p < .01, d = 0.69), CRT (p < .01, d = 0.47), COMT (p < .01, d = 0.62) and MRT (p < .001, d = 0.65) were better in the afternoon than in the morning. However, DE was not affected by the TOD (P > .05). KST improved SRT (p < .01, d = 0.078), CRT (p < .001, d = 0.72), COMT (p < .001, d = 1.31) and MRT (p < .001, d = 0.80) performances only in the morning. Cognitive performances are TOD dependent with higher performances realized in the afternoon. Performing a high intensity exercise in the morning, but not in the afternoon, enhanced several aspects of cognitive performances. The current results indicate that an intensive warm-up could be beneficial when a morning competition requires high cognitive readiness.

Heart rate variability, task load and perceived exertion associated with a long-distance military ski exercise: A pilot study

Objectives: Skiing is practiced by the security forces posted at mountain areas for patrolling, securing borders, taking up rescue missions and sometimes as recreational activities. A study was planned to assess physiological and mental stress of a military ski activity through the measurement of heart rate (HR) variability, task load and perceived exertion. Materials and Methods: Eleven healthy Indian soldiers, trained with skiing techniques, participated in a 15 km skiing with 22 kg equipment at a predetermined snowy mountainous track. Pre- and post-exercise HR and HR variability (HRV) were recorded (bio-harness, Zephyr, USA) and questionnaires, namely NASA task load index (NASA-TLX) and Borg’s rating of perceived exertion (RPE) scale, were filled after exercise. Time and frequency domain parameters such as HR, variations between successive RR intervals (RMSSD), standard deviation of RR (SDNN) and percentage value of NN50 (pNN50), low- and high-frequency bands (LF and HF %) and LF/HF ratio were derived using Kubios software. Student’s t (paired) test was applied to compare pre- and post-exercise HRV parameters and Pearson’s correlation was applied to observe interdependencies between HRV and subjective scores. Results: The findings depicted increase in post-exercise HR and decrease in overall HRV (both significant). Besides this, there was an increase in LF (significant) and LF/HF ratio (insignificant). Such response shows sympathetic dominance over parasympathetic domain of autonomic nervous system. The physical and mental stress experienced during the exercise was also expressed through high physical demand (79 out of 100) and high overall task load (total score – 77 out of 100) of the NASA-TLX and a moderately heavy RPE score (14 out of 20). Conclusion: The pre- and post-exercise differences in physiological variables ensured the presence of physical stress along with dominance of sympathetic nervous system. Overall task load was depicted with high subjective ratings. Carrying out skiing task in an environment infested with cold, wind chill, moderate hypoxia at a snowy and mountainous track possibly has induced the observed physiological and mental stress to the participants. Such findings are important to understand exact requirements of the mountain warfare events carried out by the forces.

Systematic Review and Meta-Analysis of the Relationship between Actual Exercise Intensity and Rating of Perceived Exertion in the Overweight and Obese Population.

The number of overweight (OW) and obese (OB) children, adolescents, and adults has increased globally. Exercise intensity, both actual and perceived, is a significant factor in a variety of health-related investigations and rehabilitation trainings. Despite this, literature on the connection between actual exercise intensity and the rating of perceived exertion (RPE) in overweight and obese populations is lacking. A systematic review, meta-analysis, combined analysis of variance (Brown–Forsythe ANOVA), and Spearman correlation were performed to fill this gap. After preliminary assessments, ten studies were classified as having a low risk of bias and a degree of heterogeneity (I2 = 34%; p = 0.05). The RPE scores (F = 0.032; p = 0.859), physiological index (percentage of maximal heart rate (%HRmax) (F = 0.028; p = 0.869), and percentage of maximal oxygen uptake (%VO2max) (F = 2.434; p = 0.136) demonstrated consistency without being significantly different between the normal weight (NW) and OW/OB groups. The RPE scores varied by age (NW (coefficient values) = 0.677 ***, OW = 0.585 **), as well as by indoor temperature (OW only, coefficient values = 0.422 *), body mass index (NW (coefficient values) = 0.516 **, OW = 0.580 **), and test time (NW only, coefficient values = 0.451 *). We conclude that RPE is appropriate for the following OW and OB people: (1) those who are older than 21.5 (the lowest age in the group of ≥18) years old and younger than 58.6 (the highest age in the group of ≥18) years old, without any other diseases, and (2) those who engage in low-intensity exercise while maintaining a standard indoor temperature. Future studies may address alternative techniques for increasing the reliability of longitudinal comparisons and gender comparisons, as well as investigate other possible confounding factors.

Type of self-talk matters: Its effects on perceived exertion, cardiorespiratory, and cortisol responses during an iso-metabolic endurance exercise.

Self-talk is an effective mental training technique that has been shown to facilitate or debilitate an athlete's performance, depending on its valence. Although the effects of self-talk have been supported by observing change in sport performance, little is known about how self-talk can induce physiological changes. Specifically, it is important to understand if the type of self-talk (positive, neutral, or negative) and can influence stress-related parameters, such as perceived exertion, cardiorespiratory, and cortisol responses. The study's objective was therefore to investigate the top-down effect of positive and negative self-talk compared to a dissociative activity during an iso-metabolic running exercise on autonomic regulation of cardiorespiratory function. Twenty-nine well-trained male runners [38±13years, 177±7cm and 73±7kg] volunteered to participate in a randomized-group design study that included a negative self-talk (NST), a positive self-talk, and a dissociative group (DG). First, participants underwent an incremental running test on a treadmill to determine the maximal oxygen uptake (V̇O2max ). Next, participants received a mental training session on self-talk and created three positive and three negative self-talk statements. Finally, participants underwent a 60-min steady-state running exercise on a treadmill at 70% of V̇O2max , during which they were cued at 20-, 35-, and 50-min with their personal self-created positive or negative self-talk statements while the DG listened to a documentary. Cardiorespiratory parameters and rate of perceived exertion (RPE) were recorded throughout the 60-min endurance exercise. In addition, salivary cortisol samples were obtained at waking and after treatment. Although oxygen uptake, carbon dioxide production, RPE, and heart rate significantly changed overtime during the 60-min steady-state running exercise, no significant main treatment effect was found. However, RPE scores, minute ventilation, breathing frequency, and salivary cortisol were significantly higher in the NST group compared to the two other groups. These data suggest that NST [emotion-induced stress, as reflected by elevated cortisol] altered the breathing frequency response. In conclusion, manipulating self-talk alters hormonal response patterns, modulates cardiorespiratory function, and influences perceived exertion.

The Effects of Exercise Difficulty and Time-of-Day on the Perception of the Task and Soccer Performance in Child Soccer Players.

In soccer, accurate kicking skills are important determinants of successful performance. A successful kick must meet several criteria, including speed, accuracy, and timing. In fact, players who are able to kick the ball more accurately under various difficulties, such as time pressure, space constraints, the opponent’s pressure, and the distance between the kicking point and the goal, have a clear advantage during soccer games. The aim of the present study was to investigate the effect of exercise difficulty and time-of-day on perceived task difficulty and kicking performance. Accordingly, 32 boys (age: 11 ± 0.7 years; height: 1.45 ± 0.07 m; body-mass: 38.9 ± 7.8 kg) performed shooting accuracy tests under two difficulty levels (distance (long-distance (LD) vs. short-distance (SD)) and time pressure (Without-time-pressure (WTP) vs. With-time-pressure (TP)) at 08:00 h and 17:00 h. Absolute-error, variable-error, and constant-error were evaluated during the kicking tasks, in addition to ball velocity and shooting quality. Moreover, rating-of-perceived-exertion score (RPE), feeling-scale (FS), and perceived difficulty were completed immediately at the end of each test. The results showed that shooting quality was not affected by the time-of-day, but it was better in WTP vs. TP (p < 0.05), and in SD vs. LD (p < 0.05), respectively. Higher values for FS and lower values for RPE were observed in the morning compared to the afternoon (p < 0.05) and in WTP vs. TP (p < 0.05). In conclusion, specific soccer skills of boys were not time-of-day dependent, but they may be associated with time pressure and task difficulty.

Physiological and Metabolic Requirements, and User-Perceived Exertion of Immersive Virtual Reality Exergaming Incorporating an Adaptive Cable Resistance System: An Exploratory Study.

Objective: To measure metabolic and physiological demand, subjective fatigue, and enjoyment during a signature 30-minute immersive virtual reality (IVR) adaptive cable resistance exergaming session. Methods: Fourteen healthy college-aged individuals (seven females) were initially acquainted with the IVR equipment and gameplay dynamics. Participants then underwent a 30-minute IVR exergaming session performing six different cable resistance exercises. A portable metabolic gas exchange analyzer concurrently assessed energy expenditure (EE) through indirect calorimetry while a chest-worn monitor captured heart rate (HR). Participants subsequently completed questionnaires, including the Borg scale for rating of perceived exertion (RPE), Physical Activity Enjoyment Scale (PACES), and Simulator Sickness Questionnaire (SSQ). Results: The mean EE, mean metabolic equivalent, and average total calories expended during the 30-minute session were 14.7 (standard deviation [SD] 2.8) kcal/minute, 12.9 (SD 0.5), and 440 (SD 84) kcals respectively. The mean HR was 176 (SD 3.1) beats per minute (bpm) with a mean max HR of 188 SD (SD 2.9) bpm. The combined training volume among all participants was 16,102 kg (SD 4137). Participants classified the IVR training session to be "somewhat hard-to-hard" with a RPE score of 14 (SD 1) while indicating the session to be "enjoyable" with a PACES score of 4.31 (SD 0.36). The participants did not report any cybersickness symptoms, demonstrating an average total SSQ score of 24.04 (SD 24.13). Conclusions: IVR exergaming incorporating cable resistance training elicits high EE and physiological demand with high enjoyment scores while attenuating perceived fatigue. The potential for IVR to elicit these acute training effects over long-term training periods warrants further investigation into its contribution to fitness and health.

Alternative Model for Physical Activity: Active Video Games Lead to High Physiological Responses

ABSTRACT Purpose: This study aimed to i) investigate the physiological and perceptual responses to two different active video games (AVGs), ii) compare the physiological and perceptual responses to AVGs with those encountered during classic exercise and daily sedentary routines, and iii) compare the examined variables between the sexes. Methods: Forty-three (n = 22 male, n = 21 female) volunteers participated in the study and were tested in five different conditions (resting, watching television (TV), brisk walking, AVG dancing, and AVG fighting). Oxygen consumption (VO2) and heart rate (HR) were measured continuously, whereas energy expenditure (EE) and metabolic equivalent (MET) were calculated. Rating of perceived exertion (RPE) and enjoyment scores were recorded. Results: AVG dancing and AVG fighting significantly increased VO2, MET, EE, and HR compared with brisk walking, resting, and watching TV. Comparing with brisk walking the AVG dancing yielded similar RPE and higher enjoyment scores. However, the highest physiological responses, RPE, and enjoyment scores were obtained during AVG fighting. There were significant sex x condition interactions for VO2, MET, EE, and HR. VO2, MET, and EE were significantly higher in males for all conditions, whereas HR was significantly higher in females. The mean EE values during AVG fighting and AVG dancing were 13.12 ± 2.2 kcal.min−1 and 9.69 ± 2.0 kcal.min−1, respectively in males, and 9.31 ± 1.9 kcal.min−1 and 7.07 ± 1.3 kcal.min−1, respectively in females. Conclusions: AVG dancing (MET >7) and AVG fighting (MET >9) are enjoyable, vigorous physical activities that can be recommended as an alternative home-based physical activity.

Attentional Style and Pace Monitoring on Rate of Perceived Exertion and Run Performance

Run-tracking devices are used by athletes and exercisers to monitor various metrics of human locomotion such as pace and distance. This study sought to determine the effects of pace monitoring on run performance and rate of perceived exertion (RPE). Participants were 41 (17 male, 24 female) recreationally fit runners, age 19-40 years (M = 22.4, SD = 4.4), who completed the Test of Attentional and Interpersonal Style (TAIS) to determine individual attentional focus. They then completed an associative condition (AC) 1-mile time trial and a dissociative condition (DC) 1-mile time trial 24-36 hours apart. Individual, independent t-tests compared completion time means between conditions. The internalizers group (AC) performed significantly faster in the associative condition (M = 496.10, SD = 105.05 seconds) than in the dissociative condition (M = 525.00, SD = 109.67 seconds), t(20) = 5.79, p &lt; .001. The externalizers group (DC) performed significantly faster in the dissociative condition (M = 522.70, SD = 97.37 seconds) than in the associative condition (M = 556.90, SD = 116.62), t(19) = -4.92, p &lt; .001. Results support the value of identifying an individual’s preferred attentional focus to place them in the optimal environment for success. While the study showed no significant difference in RPE scores between conditions, there may be practical implications of similar RPE scores when accompanied by significant changes in performance.

Music listening reduces biochemical and perceptual responses to a single intensified interval training

Background. Music listening is a helpful way for reduction of psychological tension state anxiety, and improvement of mood state in humans, who often experience worries, threats or anticipating stressful events. Few is known about effect of music listening on both biochemical and perceptual responses to high intensity interval training session among females practicing combat sports. The purpose of this study was to verify hypothesis that listening music during training lowers psycho-physiological stress markers. Material and methods. 16 female boxers took part in two 1-hour high intensive interval training separated 3 day apart. These sessions were of the same structures, loads, in­ten­sities. Athletes were assigned into two equal sub-groups and performed sessions with special selected dance music (MS) and without it (non-MS) Capillary blood samples were taken directly before and after training. Plasma cortisol (C), glucose (Glu) and blood lactate (LA) were determined in the samples.10-point scale was used for self-reported Rating of Perceived Exertion (RPE). Results. When the training session was accompanied music, the post-session increments of C and Glu and post-session RPE were significantly lower. The impact of music on LA was not statistically significant. Conclusions. The lowered reactivity of markers of exercise stress such as C, Glu levels and RPE scores in response to training with preferred music confirmed beneficial effect of music use in female athletes performing an intensive workout. This reduction of psychological component of exercise stress may improve a training tolerance.

Affective Responses during High-Intensity Interval Exercise Compared with Moderate-Intensity Continuous Exercise in Inactive Women.

This study aimed to investigate the effects of an acute bout of high-intensity interval exercise (HIIE) and moderate-intensity continuous exercise (MICE) on affective responses in inactive women. Thirty women with normal body mass index (BMI) and 30 women with BMI ≥ 24 kg/m2 participated in the study. All participants completed a graded exercise test and performed two exercise sessions (HIIE and MICE) in random order. Affective responses were assessed during and after each exercise session, using the rating of perceived exertion (RPE), Self-Assessment-Manikin (SAM), and Subjective Exercise Experience Scale (SEES). The results showed that the RPE scores were significantly higher in HIIE than in MICE. HIIE resulted in significantly lower pleasure scores using the SAM while arousal and dominance scores were significantly higher with HIIE compared to MICE. Positive well-being scores using the SEES were significantly lower with HIIE and both psychological distress and fatigue scores were significantly higher with HIIE. The results showed that affective responses with MICE were more positive than with HIIE, but no differences were found between normal and overweight/obese women. Based on these results, MICE may be a more acceptable exercise program for inactive women regardless of their weight status.

The effects of mass, bulk and stiffness of personal protective equipment and clothing on physical performance when performing a military mobility obstacle course

BackgroundSoldiers are required to conduct tasks and operations in physically demanding situations, where the ability to move (mobility) quickly is important to lethality and survivability.This study employed a specially designed suit to try to isolate the main mass property characteristics of personal protective clothing/equipment (PPCE) including mass, bulk and stiffness as much as possible and evaluated their effects on soldier performance across operationally-relevant mobility tasks. MethodEight male military subjects performed the load effects assessment program (LEAP) obstacle course while wearing 7 different configurations of specifically designed suit: unencumbered (control), 10 kg mass, 30 kg mass, 20 L bulk, medium stiffness, high stiffness and a mixed configuration consisting of 10 kg mass, 20 L bulk and medium stiffness. The primary outcome measure was total LEAP completion time. Additionally, heart rate, rating of perceived exertion (RPE), range of motion and vertical jump heights were measured and related to LEAP performance. ResultsAll configurations degraded or tended to degrade the total LEAP completion times (p-value < 0.05), except for the medium stiffness configuration. Heart rate did not differ significantly between configurations, while RPE scores of configurations 30 kg and mix were significantly higher compared to control (p < 0.01). ConclusionMass, bulk and stiffness all negatively influence LEAP obstacle performance. Therefore, all three have to be considered when trying to reduce the physical burden on soldiers.

Velocity Change Estimation by Subjective Measures Over a Wide-Load Spectrum in Squat and Bench Press.

Chapman, M, Larumbe-Zabala, E, Triplett, NT, and Naclerio, F. Velocity change estimation by subjective measures over a wide-load spectrum in squat and bench press. J Strength Cond Res 35(2S): S51-S56, 2021-This study compared whether the perception of effort measured on a repetition-by-repetition basis during continuous sets to failure is different between squat (SQ) and bench press (BP). After determining the one repetition maximum (1RM) value in both SQ and BP, 18 subjects (28.2 ± 5 years, 50% women) performed 7 sets to failure per exercise, separated by 24-48 hours, alternating SQ and BP, using the following relative load ranges: 30 < 40%, 40 < 50%, 50 < 60%, 60% < 70%, 70 < 80%, 80 < 90%, and >90%. The mean accelerative velocity (MAV) and rating of perceived exertion (RPE) using the OMNI-RES (0-10) scale were measured for every repetition of each set. The ability of the OMNI-RES (0-10) scale to identify velocity changes during continuous sets to volitional failure and to distinguish loading zones divided into 10% slots, from 30 to 100% of 1RM was confirmed for both SQ and BP. The RPE values measured at (a) the first repetition; (b) the repetition where MAV peaks; (c) the repetition where MAV drops by ≤10% compared the maximum and (d) the last repetition, showed no differences (p > 0.05, d < 0.2) between exercises. In conclusion, the same RPE scores can be applied to both exercises, for either estimating the relative load or monitoring changes in MAV during continuous sets to failure.

Physiological Effects of N95 FFP and PPE in Healthcare Workers in COVID Intensive Care Unit: A Prospective Cohort Study.

BackgroundHealthcare workers (HCWs) are at increased risk of exposure to severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). Personal protective equipment (PPE) is mandated for HCWs. However, the physiological effects on the HCWs while working in the protective gear remains unexplored. This study aimed to assess the physiological effects of the prolonged use of PPE on HCWs.Materials and methodsSeventy-five HCWs, aged 18–50 years were enrolled in this prospective, observational, cohort study. The physiological variables [heart rate, oxygen saturation, and perfusion index (PI)] were recorded at the start of duty, 4 hours after wearing N95 filtering facepiece respirator (FFR), pre-donning, and post-doffing. The rating of perceived exertion (RPE) score and modified Borg scale for dyspnea was evaluated. The physiological variables were represented as the mean ± standard deviation. Wilcoxon signed-rank test was used to show any difference in RPE and modified Borg scale for dyspnea. A p value of <0.05 was considered significant.ResultsThere is a statistically significant difference in the physiological parameters post-doffing compared with baseline: Heart rate (p < 0.001); oxygen saturation (p < 0.001); PI (p < 0.001). RPE score showed increased discomfort with continuous use of N95 FFR. However, exertion increased only marginally. The major adverse effects noted with PPE use were fogging, headache, tiredness, difficulty in breathing, and mask soakage, with a resultant mean duration of donning to be 3.1 hours.ConclusionThe use of PPE can result in considerable changes in the physiological variables of healthy HCWs. The side effects may lead to excessive exhaustion and increased tiredness after prolonged shifts in the intensive care unit (ICU) while wearing PPE.How to cite this articleChoudhury A, Singh M, Khurana DK, Mustafi SM, Ganapathy U, Kumar A, et al. Physiological Effects of N95 FFP and PPE in Healthcare Workers in COVID Intensive Care Unit: A Prospective Cohort Study. Indian J Crit Care Med 2020;24(12):1169–1173.

Use of Rating of Perceived Exertion-Based Training Load in Elite Ice Hockey Training and Match-Play.

Rago, V, Vigh-Larsen, JF, Deylami, K, Muschinsky, A, and Mohr, M. Use of rating of perceived exertion-based training load in elite ice hockey training and match-play. J Strength Cond Res 36(10): 2837-2843, 2022-Training load (TL) based on the subjective rating of perceived exertion (RPE) may be a useful athlete monitoring alternative when wearable technology is unavailable. The aim of this study was to examine the validity of RPE-based TL monitoring in elite ice hockey. A male ice hockey team ( n = 18) was monitored using a 200-Hz accelerometer, heart rate (HR) and RPE (0-10 scale), throughout a 4-week competitive period ( n = 309 individual observations). Session-RPE (RPE × duration) averaged 244.8 ± 135.2 and 728.6 ± 150.9 arbitrary units (AU) during practice sessions and during official games, respectively. The smallest worthwhile change was 19.8 AU. Within-individual correlations between session-RPE and total accelerations >0.5 m·s -2 (Acc tot ), accelerations >2 m·s -2 (Acc2), total decelerations >-0.5 m·s -2 (Dec tot ), decelerations < -2 m·s -2 (Dec2), time > 85% maximum HR, Edwards' TL, and modified training impulse were very large ( r = 0.70-0.89; p < 0.001). In addition, correlations between RPE and measures of exercise intensity (Acc tot per min, Acc2 per min, Dec tot per min, mean HR, and peak HR) were small ( r = 0.02-0.29; p < 0.05) except for Dec2 being unclear ( p = 0.686). Differences in intensity parameters between RPE range (easy to very hard, 2-7 AU) were small ( r = 0.22-0.31; p < 0.05). The session-RPE method can be used as a global indicator of TL in ice hockey. Specific ranges of time-motion and HR intensity variables can be demarcated between RPE categories (easy to very hard; 2-7 AU). Accounting for training volume (session-RPE) more accurately reflects objective methods of TL based on accelerative efforts and HR, than the RPE score (based on the perception of the intensity).

Effect of Ramadan intermittent fasting on cognitive, physical and biochemical responses to strenuous short-term exercises in elite young female handball players

The present study aimed to assess the effect of Ramadan intermittent fasting (RF) on cognitive and physical performance and biochemical responses to specific exercises in elite young female handball players. Twelve athletes participated in three experimental sessions: one week before Ramadan (BR), during the first week of Ramadan (FWR) and during the last week of Ramadan (LWR). The present crossover study was carried out in Tunisia during the 2013 Ramadan month lasting from 9 July to 7 august. During each session, a battery of tests was performed as follow: Hooper index, vigilance test (VT), Epworth sleepiness scale (ESS), five jump test (5-JT), modified agility T-test (MAT), maximal standing ball-throw velocity test (MSBVT) and Running-based Anaerobic Sprint (RAST) Test. Rating of perceived exertion (RPE) was recorded immediately after the RAST. Blood samples were collected before and after exercises during each session. The results showed that ESS scores were higher during LWR than BR (p < 0.05). Moreover, MSBVT time decreased (p < 0.05) during LWR, therefore performance enhanced. The power of three final sprints from the RAST decreased significantly only during LWR compared to BR (p < 0.05). RAST fatigue index and RPE scores were higher during LWR more than BR (p < 0.05). The results showed also that hematological measures (i.e., red blood cells, hemoglobin and hematocrit), plasma osmolarity and energetic markers were unaffected by RF. Biomarkers of muscle damage were higher after the RAST only during LWR compared to BR (p < 0.01 for all). In conclusion, RF increased ESS and decreased RAST performances associated with higher muscle damage and fatigue, especially at LWR. These previous alterations could be attributed to disturbances of sleep and circadian rhythms rather than nutritional deficiency or dehydratation.

Real-time indicators and influence factors of muscle fatigue in push-type work

Muscle fatigue is a significant cause of musculoskeletal injury and can easily induce unsafe behaviour. Push-type work is a common type of physical work, and if not designed appropriately, may lead to muscle fatigue. Previous studies on muscle fatigue mainly focus on investigating continuous force exertion, and in most of them, a constant muscle force is assumed, thereby ignoring the fluctuations present in exertion. In this study, bolt hole drilling was chosen to represent typical push-type work, and the muscle fatigue from this work was examined. The experimental system designed in this study monitored the muscle force in real time. In the experiments, different thrust angles (15°, 45°, and 75°), different relative force values (20% MVC, 40% MVC, and 60% MVC; MVC: maximum voluntary contraction) and different working time intervals (0 s, 30 s, 60 s, and 90 s) were considered. The results demonstrate that there is a significant positive correlation between the rating of perceived exertion (RPE) and muscle force attenuation (r = 0.786, p = 0). The cubic regression model (Y = − 0.00071x3 − 0.024x2 − 0.334x + 1.146, R2 = 0.639) fits the data most closely. Therefore, force attenuation can be used as a real-time indicator of muscle fatigue. In addition, the relative force value and thrust angle have a significant impact on the RPE score, whereas the working time interval has no major effect on it. This study provides a new method for evaluating muscle fatigue and a basis for the design of push-type work to reduce fatigue-induced accidents and musculoskeletal injuries.

A warm-up performed with proper-weight sandbags on the leg improves the speed and RPE performance of 100 m sprint in collegiate male sprinters.

Muscle performance can be notably improved following a preloading maximal or near maximal stimulus due to the induction of postactivation potentiation, but the success of a preloading exercise in generating a postactivation potentiation response depends on the balance between fatigue and potentiation. However, the optimal warm-up strategy for sprint runners before a match may be not well established until now. Fifteen well-trained male sprint runners performed four different warm-up protocols: warm-up with 0% body mass; warm-up with 2% body mass; warm-up with 4% body mass; warm-up with 8% body mass. The weight-bearing sandbag was tied about 3~5 cm above each ankle joint. During the 100-meter test, the time and rating of perceived exertion (RPE) in the first 30 meters, time in the first 60 meters, and time in the 100 meters were recorded, respectively. Two-high-speed digital video cameras were separately set in the sagittal planes on the left side of a line drawn at a distance of 30 m and 60 m from the start line to record the sprint motion. A warm-up performed with a sandbag weighted 4% of body mass could significantly improve the time and the RPE score of 100 m sprint by improving average velocity, stride frequency, average stride length, and average accelerated velocity during the sections of 0~30 m, 30~60 m and 60~100 m. This positive effect was better than that of 2% body-weigh effect. However, a warm-up performed with a sandbag weighted 8% of body mass had no significant influence on the performance of a 100 m sprint. Current results indicated that a warm-up performed with proper-weight(4% body mass) sandbags on the leg was beneficial to the improvement of 100 m sprint performance, and the mechanism might be that it effectively activated the main muscles and neuromuscular regulation of running and produced a better postactivation potentiation.

Methods for Regulating and Monitoring Resistance Training.

Individualisation can improve resistance training prescription. This is accomplished via monitoring or autoregulating training. Autoregulation adjusts variables at an individualised pace per performance, readiness, or recovery. Many autoregulation and monitoring methods exist; therefore, this review’s objective was to examine approaches intended to optimise adaptation. Up to July 2019, PubMed, Medline, SPORTDiscus, Scopus and CINAHL were searched. Only studies on methods of athlete monitoring useful for resistance-training regulation, or autoregulated training methods were included. Eleven monitoring and regulation themes emerged across 90 studies. Some physiological, performance, and perceptual measures correlated strongly (r ≥ 0.68) with resistance training performance. Testosterone, cortisol, catecholamines, cell-free DNA, jump height, throwing distance, barbell velocity, isometric and dynamic peak force, maximal voluntary isometric contractions, and sessional, repetitions in reserve-(RIR) based, and post-set Borg-scale ratings of perceived exertion (RPE) were strongly associated with training performance, respectively. Despite strong correlations, many physiological and performance methods are logistically restrictive or limited to lab-settings, such as blood markers, electromyography or kinetic measurements. Some practical performance tests such as jump height or throw distance may be useful, low-risk stand-ins for maximal strength tests. Performance-based individualisation of load progression, flexible training configurations, and intensity and volume modifications based on velocity and RIR-based RPE scores are practical, reliable and show preliminary utility for enhancing performance.