Mean Rating Of Perceived Exertion Research Articles

Leg and walking self-exercise (LAWS) program for older adults with cancer during treatment.

e24009 Background: Regular aerobic and resistance exercise during cancer treatment is recommended by guidelines. We developed Leg And Walking Self-exercise (LAWS), a self-directed exercise program informed by the Exercise Is Medicine initiative. The acceptability and feasibility of the LAWS program was evaluated in older adults with advanced cancer during treatment. Methods: This was a prospective study of 40 consecutive older adults who received comprehensive geriatric assessment (CGA) at a geriatric oncology service (GOS) and started a new line of systemic therapy for advanced cancer on a medical oncology floor over a 1-year period. The LAWS consists of three leg exercises (sit-to-stand, calf raise, and knee extension) and walking. We set three intensity levels for the leg exercises based on a number of repetitions per day and for walking based on minutes per day as follows: level 1 = 10, level 2 = 20, level 3 = 30. We instructed patients to adjust the intensity level with a goal rating of perceived exertion (RPE) of 3 or 4 on a 0–10 scale, where 0 = no exertion and 10 = maximal exertion, and encouraged them to do both leg resistance training and walking every day. The LAWS program was introduced to a patient by the GOS during CGA consultation. When the patient was admitted to a medical oncology floor, a nurse went over the LAWS program and gave an exercise diary to the patient. During inpatient stay, a nurse checked exercise diary and helped the patient keep the diary as needed. Upon discharge from hospital, a nurse instructed the patient to continue the LAWS at home and maintain an exercise diary. Adherence was quantified as the proportion of patients who performed the LAWS program at least level 1 intensity more than 50% of each study period. Patient perspectives on the LAWS program were evaluated using the Acceptability of Intervention Measure (AIM) and the Feasibility of Intervention Measure (FIM). A summary score of each measure ranges from 1 to 5 (higher is better). Results: Mean age was 78 years and 48% had colorectal cancer. Overall, 28% of patients were fit, 53% were pre-frail, and 20% were frail based on a CGA. During hospitalization, 63% of the patients adhered to both leg exercise and walking: on average, over 12 days in hospital, 2.8 leg exercises, 23 repetitions a day, 5.6 days/week, with a mean RPE of 3.0 (low intensity) and 19 minutes of waking a day, 4.9 days/week, with a mean RPE of 3.0. During the period between discharge and first outpatient appointment, 71% of patients adhered to the LAWS program: on average, over 11 days at home, 2.6 leg exercises, 22 repetitions a day, 5.9 days/week, with a mean RPE of 3.0 and 22 minutes of waking a day, 5.4 days/week, with a mean RPE of 3.2. Patients reported high acceptability (AIM mean score = 4.2; SD = 0.7) and feasibility (FIM mean score = 4.2; SD = 0.5) of the program. Conclusions: The LAWS is an acceptable and feasible self-directed exercise program for older adults with advanced cancer receiving treatment.

Ventilatory Threshold Related to V̇O2reserve, Heart Rate Reserve and Rating of Perceived Exertion in a Large Varied Sample.

ACSM guidelines state that aerobic exercise intensity should be 30/40-89% V̇O2reserve (V̇O2R) or heart rate reserve (HRR). Determining the proper intensity within this range is the "art" of exercise prescription, often relying on rating of perceived exertion (RPE) as the adjunctive intensity modulator. Current guidelines do not consider the use of ventilatory threshold (VT) due to the need for specialized equipment and methodological issues. The purpose of this investigation was to evaluate VT related to V̇O2peak, V̇O2R, HRR and RPE across the full spectrum of very low to very high V̇O2peak values. 863 records of exercise tests were retrospectively examined. Data were stratified for V̇O2peak, activity level, age, test modality and sex. When stratified for V̇O2peak, V̇O2 at VT (V̇O2vt) had a lower mean value of ~14 ml•kg-1•min-1 in the lowest fit, rose gradually until median V̇O2peak, and rose steeply thereafter. When graphed relative to V̇O2peak; V̇O2 at VT as a % of V̇O2R (VT%V̇O2R) resembled a U-shaped curve, with a nadir ~43% V̇O2R, at V̇O2peak ~ 40 ml•kg-1•min-1. Average VT%V̇O2R increased to ~75% in groups with the lowest or highest V̇O2peak. There was a large variance in the value of VT at all V̇O2peak levels. Mean RPE at VT was 12.5 ± 0.93, regardless of V̇O2peak. Given the relationship of VT as the transition from moderate- to higher-intensity exercise, these data may help the undertanding of aerobic exercise prescription in persons across the spectrum of V̇O2peak values.

Pre-workout supplementation of capsaicin does not increase resistance training performance in a multiexercise protocol in trained men

Purpose.The aim of this study was to investigate the acute effect of capsaicin supplementation on performance, perceived exertion, and perceived effects in a resistance training protocol for the lower body.Methods.The sample was 14 young men (22.21 ± 2.55 years; 82.35 ± 5.16 kg; 174 ± 0.7 cm; 9.08 ± 2.73% of body fat), with 4.19 ± 2.98 years of experience in resistance training. The study design was randomised, double-blind and crossover. The subjects performed the training protocol after consuming Capsaicin (12 mg) (CAP) or a placebo (PLA). The training protocol was: five sets of Back Squats and Leg Presses 45°, with 70% of 1RM until failure. The interval between sets was 90 seconds and 120 seconds between exercises. The number of maximum repetitions (NMR) and the rate of perceived exertion (RPE) were recorded after each set.Results.The paired t-test showed that there was no statistically significant difference between PLA and CAP in the mean NMR (<i>p</i> = 0.251; 95%CI = –5.47 – 19.18), mean session volume load (VL) (weight lifted × NMR) (<i>p</i> = 0.117; 95%CI = –582.70 – 4639.99) and in the mean RPE (<i>p</i> = 0.458; 95%CI = –0.81 – 0.39).Conclusions.The acute capsaicin supplementation did not change the perception of vigour and side effects. Therefore, pre-workout capsaicin supplementation did not alter performance, RPE, or perceived effects in a lower body multi-exercise training protocol in trained men.

Long-Term Analyses of the Rate of Perceived Exertion as an Indicator of Intensity in Women's Basketball during a Relegation Play-off.

Knowledge of internal load is essential to understand the effect of training and competition on athletes. The aim of this study was to analyse the validity of the rate of perceived exertion (RPE) scale as an indicator of intensity in amateur female basketball players during a relegation play-off. The heart rate and RPE of 10 players (age: 21.30 ± 2.71 years, weight: 68.84 ± 11.21 kg, body fat: 20.74 ± 3.51%) from a Copa Catalunya team while competing over a 10-day period were analysed. The mean heart rate of each match was registered with the Suunto Team Pack™ heart rate monitors. The RPE values were obtained once the match ended, completing the original Borg scale. The mean RPE ranged from 15.20 ± 2.39 to 18.00 ± 1.07 AU, whereas the mean heart rate (MHR) ranged from 132.35 ± 12.37 to 147.33 ± 10.61 bpm. There was also an improvement in the statistical correlation between the two variables as the days progressed. Regression equations were calculated for the total number of registered matches and the last five matches, obtaining the following regression equations: MHR = 6.23 × RPE20 + 36.8 (R2 = 0.56) for all games and MHR = 30.95 + 6.73 × RPE (R2 = 0.73) for the last five games. The results suggest that RPE could be seen as an indicator of intensity in amateur basketball players during a relegation play-off, improving their relationship with MHR as the weeks went by, which could suggest a learning process.

Comparison of physical demanding paramedic work tasks between an Australian and Canadian ambulance service

Ambulance services require candidates to pass physical employment tests (PETs) to be deemed suitable for the paramedic role. Whilst some research has been undertaken to improve to relevance of these tests, they are often arbitrary and not based on research. The first phase in developing PETs is to generate a list of job tasks. To examine the utility of universal physical tasks tests for ambulance work, we conducted a cross-sectional study, utilising the results from previous work in a Canadian ambulance service to create a physical tasks checklist. These lists were then used by paramedics working for an Australian Service to identify physical tasks in their workplace, and the results from the two services were compared. Patient transfer tasks were similar in frequency and description for both services. Stretcher handling and manoeuvring was identified by Canadian paramedics as highly strenuous, (mean rating of perceived exertion (RPE) 7/10) but were rated mean RPE <3/10 by AV paramedics.Although some tasks between these two services were similar, the ambulance services in this study differed sufficiently with regard to equipment, training and policies mean that similarly titled jobs are not comparable, cross-nationally. Service specific job task analysis is required to develop PETs that ensure employees are specifically selected to meet the requirements of that service.

Match characteristics of professional outfield amputee soccer players during official amputee soccer matches

Objective: The objective of this study was to investigate physiological responses and movement profiles of amputee soccer players during official matches. Material and Methods: Five outfield amputee soccer players with a 9.20±0.81 years of amputee soccer experience (age 28.60±5.32 years; height 1.71±0.05 m; body mass 71.54±9.39 kg) volunteered for this study. Physiological responses [blood lactate (BLa), heart rate (HR) and ratings of perceived exertion (RPE)] and activity profiles [peak speed, total distance covered (TD), TD at five speed categories (SC), percentages of TD at five SC and time spent in four maximal heart rate (HRmax) zones] were analyzed during seven official amputee soccer matches. Results: Mean game BLa, RPE, HR and HRmax were 5.58±1.63 mmol.L-1, 9.43±2.62, and 151.77±16.05 bpm and 180.74±9.23 bmp, respectively. HRmax was higher in the first half than in the second half (p=0.02). Players covered 102.62±7.24 m.min-1 and this did not change between the halves during amputee soccer matches (p=0.40). TD at very low SC was 73.86±0.57 m.min-1 whereas TD at very high SC accounted only for 0.24±0.04 m.min-1. Similarly, the percentage of the TD at very low SC was 70.18±10.30% and the percentage of the TD at very high SC was 0.24±0.04%. Amputee soccer players spent ~31 min and ~15 min at high intensity and moderate HRmax zones, respectively. These accounted only about ~5 min at very low and low intensity HRmax zones during whole matches. Conclusion: These results showed that amputee soccer played at the professional level is a high-intensity exercise, which could be used to prescribe amputee soccer specific training regimes.

Development of a functional assessment task in metastatic breast cancer patients: the 30-second lie-to-sit test

Purpose To develop a physical function test based on lie-to-sit transition and to study its feasibility in patients suffering from metastatic breast cancer (MBC). Materials and methods This cross-sectional study recruited 90 women diagnosed with MBC. Patients were asked to transfer from lying to sitting position as fast as possible during 30 s, performing the 30-second lie-to-sit test (30-LTS). Heart rate (HR), rate of perceived exertion (RPE) and number of repetitions were measured. An assessment included the 30-second sit-to-stand test (30-STS), handgrip strength, Upper Limb Functional Index (ULFI) and Lower Limb Functional Index (LLFI). Pearson correlation was calculated between 30-LTS and independent outcomes. A linear regression model explaining the 30-LTS results was further constructed with variables that had a significant correlation. Results About 72 patients were measured, of which 65 were able to perform 30-LTS. Subjects performed 8.13 repetitions on average, with a mean RPE of 4.78 (0–10), reaching 63.08% of maximal HR. 30-LTS was significantly correlated with 30-STS (r = 0.567), handgrip (p = 0.26) and LLFI (r = 0.348). The regression model was significant (F = 4.742; p = 0.00), and these variables explained 32% of the variance of the 30-LTS. Conclusion The 30-LTS showed to be a feasible functional and submaximal test in a sample of MBC. IMPLICATIONS FOR REHABILITATION The 30-second lie-to-sit (30-LTS) developed does not require the patient to acquire a standing position and therefore it is an alternative to other more biomechanically demanding tests such as a 30 second sit-to-stand test or Timed up-and-go. 30-LTS involves both a functional and energy system assessment tool that can be implemented by allied health professionals in oncology rehabilitation to individualize exercise prescription, as well as for functional screening purposes. The present study adds value to current research focused on individualizing exercise prescription in the oncology field and provides reference values of function in metastatic breast cancer patients.

Physiological response during match simulation in youth soccer players

Introduction: The aim of this study was to investigate physiological changes of heart rate (HR), rating of perceived exertion (RPE) and vertical jump (VJ) height responses during a Youth Soccer Match Simulation (YSMS90).Materials and Methods: Twenty (n = 20) male academy soccer players (age:17 ± 2 years, height: 1.69 ± 0.6, weight: 67.9 ± 6 kg) volunteered for this study. In a repeated measures study design, each participant completed the 90 min of soccer match simulation. Heart rate, subjective RPE and VJ were recorded every 5 min throughout the simulation.Results: The mean HR, RPE and VJ height during the YSMS90 were 147 ± 19 beats/min, 16 ± 1 and 34 ± 4 cm, respectively. There was a significant increase of HR and RPE throughout the YSMS90. The VJ performance reduced during the second half of the simulation.Conclusions: The findings from this study suggest that YSMS90 elicited similar physiological responses to soccer match play and may justify the use of YSMS90 for replicating the demands of youth soccer as an ecologically valid soccer match play simulation.

Adaptive High-Intensity Exergaming: The More Enjoyable Alternative to Conventional Training Approaches Despite Working Harder.

Objective: The purpose of this study was to assess psychological and physiological responses to an exergaming session in the ExerCube (EX) and compare them with the responses of a moderate endurance run (ER). Materials and Methods: Twenty-eight healthy adults (13 women) aged 24.8 ± 3.8 years took part in this study. The first test day, participants performed a graded exercise test on a treadmill to determine maximal heart rate (HR) and lactate levels. The following test days 2 and 3, the participants completed an EX session and an ER on a treadmill in a randomized counterbalanced order. HR, rate of perceived exertion (RPE), and lactate levels were assessed during both sessions. After the sessions, the participants completed the "Physical Activity Enjoyment Scale" and the "Flow Short Scale." Results: The analysis of variance revealed that enjoyment (P = 0.036), flow (P = 0.042), RPE (P = 0.005), as well as mean and peak HR (P < 0.001) during the EX session were significantly higher compared with the ER. Gender did not affect the differences between the two conditions for mean HR (P = 0.61), maximal HR (P = 0.122), RPE (P = 0.862), flow (P = 0.376) nor enjoyment (P = 0.867). During the EX session, the lactate levels of all participants exceeded the individual lactate threshold (LT). During the ER, lactate values remained below the LT. Conclusion: The ExerCube presents both a physiological relevant exercise stimulus and a joyful gaming experience. Despite the higher exercise intensity achieved during the EX session, enjoyment was significantly higher compared with the ER. Therefore, the EX can be a promising and appealing tool to facilitate physical activity. Trial registration: ISRCTN registry, ISRCTN43067716, April 14, 2020. Trial number: 38154.

Influence of Warm-Up Music Preference on Anaerobic Exercise Performance in Division I NCAA Female Athletes.

The purpose of this study was to investigate the effects of listening to preferred versus non-preferred warm-up music on anaerobic sprint performance in Division I NCAA female athletes. Female collegiate athletes (n = 14) were recruited for this study. In a counterbalanced, crossover study design, participants completed two separate visits, each with a different warm-up music condition: preferred (Pref) or non-preferred (Non-pref). During each visit, participants completed a 3 min standardized cycling warm-up at 50 Watts while listening to Pref or Non-pref music. Following this, participants completed 3 × 15 s Wingate Anaerobic Tests (WAnTs) with a 2 min active recovery period in between tests. Motivation to exercise was measured immediately following the warm-up (WU), WAnT1, WAnT2, and WAnT3. The rate of perceived exertion (RPE) was also measured after each WAnT. Each visit was separated by a minimal recovery period of 48 h. Mean power, total work, RPE, and motivation were analyzed. Mean power (p = 0.044; d = 0.91) and total work (p = 0.045; d = 0.78) were significantly higher during the Pref music condition versus Non-pref. RPE remained unchanged regardless of condition (p = 0.536; d = 0.01). Motivation was significantly higher with Pref warm-up music compared to Non-pref (p < 0.001; d = 1.55). These results show that listening to Pref warm-up music has an ergogenic benefit during repeated sprints in comparison to Non-pref music and improves motivation to exercise. Listening to warm-up music prior to high-intensity repeated exercise may aid in optimizing performance and training in collegiate athletes.

The Effect of Different Doses of Acute Normobaric Hypoxia on Sprint Interval Training and Cognitive Performance

Purpose To determine the effects of different doses of acute normobaric hypoxia on sprint interval training (SIT) and cognitive performance (CP) in male and female athletes. Methods: In this double-blind, randomized, counterbalanced, crossover study, participants (13 men, 13 women) performed 6 x 15-sec maximum effort SIT training with two minutes active recovery between sprints on a cycle ergometer in normoxia (NOR, 0 m), moderate hypoxia (MH, 2,500 m), and high hypoxia (HH, 3,500 m) while wearing face masks and without using the face mask as a control condition (CON). The peak and mean power, CP, blood lactate (BL), heart rate (HR), and the rating of perceived exertion (RPE) were measured pre- and post-SIT and at various time points during the experimental protocol. Results: We did not observe any change in the peak and mean power, CP, HR, and RPE between trials and genders (p>0.05). However, in the HH, the post-test BL was significantly higher for both genders than the CON condition (p=0.034, p=0.025) and NOR (p=0.11, p=0.034). Conclusions: This study showed that different hypoxia doses did not affect SIT and cognitive performance and did not differ between genders.

Investigating the effect of mouth guard use on aerobic performance in amateur boxers.

ObjectivesTo assess if wearing a mouth guard impacts maximal aerobic capacity in amateur boxers.Materials and MethodsA prospective crossover cohort (pilot) study was conducted to assess maximal aerobic capacity in amateur boxers using the 20 m multi stage fitness test (MSFT). Two primary outcomes measures were recorded: (1) the maximum oxygen uptake (peak VO2—mL/kg/min) and (2) distance run (meters—m). Thirteen amateur boxers completed the MSFT 7 days apart under control (no mouth guard—C) and intervention conditions (mouth guard—MG). Participants also submitted data on height, weight, type of mouth guard and Rate of Perceived Exertion (RPE) during the test.StatisticsPaired T‐test.ResultsMouth guard use was shown to reduce peak VO2 and distance run during the 20 m MSFT from 56.31 to 54.12 mL/kg/min and 2572 to 2380 m respectively (p < 0.05). Twelve out of 13 participants wore a Boil & Bite mouthguard and recorded lower peak VO2 scores (−4.38%) when wearing a mouth guard compared to control conditions, (Mean = −2.46 mL/kg/min, Range of decrease = 4.2–0.9 mL/kg/min; p < 0.05). Ten participants submitted data on RPE—One participant with a custom made mouthguard reported no change in RPE in mouthguard conditions, while nine participants reported an average (+30.5%) increase in mean RPE in Boil & Bite mouthguard conditions compared to control conditions.ConclusionsBoil & Bite mouth guard use was shown to significantly reduce aerobic performance in amateur boxers and increase the perceived rate of exertion during the 20 m MSFT.

Ratings of perceived exertion at the ventilatory anaerobic threshold in people with coronary heart disease: A CARE CR study.

Exercise prescription guidelines for individuals undergoing cardiovascular rehabilitation (CR) are often based on heart rate training zones and rating of perceived exertion (RPE). United Kingdom guidelines indicate that patients should exercise at an intensity of RPE 11 to 14. We aimed to determine the accuracy of this approach by comparing this RPE range with an objectively measured marker of exercise intensity, the ventilatory anaerobic threshold (VAT), and examine whether baseline directly determined cardiorespiratory fitness (CRF) affects the association between VAT and RPE. Participants underwent a maximal cardiopulmonary exercise test before an 8-week community-based CR programme. Peak oxygen uptake (V̇O2peak) and VAT were recorded, and RPE at the workload at which VAT was identified was recorded. Data were then split into tertiles, based on VO2peak, to determine whether RPE at the VAT differed in participants with low, moderate or higher CRF. We included 70 individuals [mean (SD) age 63.1 (10.0) years; body mass index 29.4 (4.0)kg/m2; 86% male]. At baseline, the mean RPE at the VAT (RPE@VAT) was 11.8 (95% confidence interval 11.0-12.6) and significantly differed between low and high CRF groups (P<0.001). The mean RPE@VAT was 10.1 (8.7-11.5), 11.8 (10.5-13.0), and 13.7 (12.5-14.9) for low, moderate and high CRF groups, respectively. When using RPE to guide exercise intensity in CR populations, one must consider the effect of baseline CRF. Mean RPEs of ∼10, 12 and 14 correspond to the VAT in low, moderate and higher-fit patients, respectively.

Abstract P174: Value Of Six Minute Walk Test In The Evaluation Of Children With Elevated Blood Pressures

Lifestyle modifications, a mainstay of hypertension (HTN) therapy, include recommendations for regular physical activity. However, fitness is not typically assessed. In the HTN clinic at Seattle Children’s, we conduct the 6-minute walk test (6MWT) in children &gt; 6 yrs referred for HTN. We sought to assess whether children referred for HTN underperform on the 6MWT. Methods: We performed a retrospective chart review of patients seen from 9/1/18 - 9/30/19 who completed an ambulatory blood pressure monitor (ABPM) and 6MWT. Chart review included ABPM results, age, sex, BMI z-score, self-reported physical activity (RepPA) levels, rating of perceived exertion (RPE) and comorbid conditions. Exclusion criteria included lack of ABPM, 6MWT or compromised exercise capacity. ABPM was classified according to the 2014 AHA guidelines and 6MWT was compared to normative datasets. Fisher’s Exact test was used to compare the distributions of distance from mean values for the 6MWT and ANOVA was used to compare mean BMI z-score and RPE among groups. Linear regression assessed 6MWT with HTN status, adjusted for age, sex, and BMI z-score. Results: Demographics and clinical measures are summarized in Table 1. RepPA, 6MWT and RPE did not differ significantly. Most children underachieved regardless of group; the distance walked was &gt; 2 SD below mean in 31 of 52 (60%). BMI z-score was significantly higher in the abnormal ABPM group. Linear regression showed no effect of HTN status. Conclusion: Most children underperformed on the 6MWT and results did not differ based on HTN status. This study suggests the 6MWT is useful to assess fitness in this population and serves as baseline for comparison.

Wheelchair Basketball Exercise Intensity in Youth

Children and youth with physical disabilities are at the greatest risk for inactivity, emphasizing the need for evidence-based activity options in recreation, rehabilitation, and post-rehabilitation settings. To determine if a wheelchair sport enabled youth participants to sustain moderate to vigorous physical activity (MVPA), the primary purpose of this study was to document exercise intensity of wheelchair basketball (WBB) among youth. The secondary purpose was to examine the influence of age, disability type, and training condition on intensity. Thirty-four youth with physical disabilities (MAge = 15.73 ± 2.57 yrs; MPlaying Experience = 4.32 ± 2.77 yrs) participated in three wheelchair basketball training sessions that included tactical drills (M = 113 min), and scrimmage (M = 57 min) training conditions. Percentage of maximum heart rate (HRMax), mean accelerometer vector counts per minute, and rate of perceived exertion (RPE) were assessed across 3 practices and collapsed into one training intensity score for each variable. Mean HRMax was 66±8% and mean accelerator vector counts were 6,055±1439 per minute, indicating that participants sustained MVPA during WBB training. Perceived effort, however, was distinct from the actual physical demand as mean RPE was 3.1±1.5. Age did not influence intensity scores but players who had a congenital or acquired spinal cord injury and were participating in scrimmage activity demonstrated higher exercise intensity. These findings support the ability of youth WBB players to sustain MVPA. This activity can be recommended as an evidence-based initiative in sport, rehabilitation or post-rehabilitation settings.

Mechanical, Physiological, and Perceptual Demands of Repeated Power Ability Lower-Body and Upper-Body Tests in Youth Athletes: Somatic Maturation as a Factor on the Performance.

This study aims (a) to assess and compare the acute mechanical, physiological, and perceptual demands induced by a lower and upper body repeated power ability (RPA) protocols, and (b) to examine how the somatic maturation could predict training response in RPA. Thirteen young male basketball players (chronological age = 15.2 ± 1.1 years; height = 173.8 ± 9.5 cm; body mass = 71.7 ± 18.3 kg) were selected to perform the parallel Back Squat (BS), and Bench Press (BP) RPA protocols (3 blocks of 5 sets of 5 repetitions with 30 s and 3 min of passive recovery between sets and blocks, respectively). Mean propulsive power (MPP), accelerometer-based data, cardio-respiratory data, blood lactate, rate of perceived exertion (RPE) and muscle soreness were recorded. Somatic maturation was estimated according to the Khamis and Roche method. On the BS protocol, the mean oxygen uptake (VO2), heart rate (HR), and RPE were 1006.33 ± 481.85 ml/min., 133.8 ± 12.5 bpm, and 6.14 ± 0.98 A.U., while on the BP protocol, were 684.6 ± 246.3 ml/min., 96.1 ± 10.4 bpm, and 5.08 ± 1.44 A.U., respectively. Significant between-blocks differences were found for MPP, RPE, and blood lactate for both exercises. The BS implies higher cardio-respiratory and perceptual demands, though lower power production fluctuation and movement variability than the BP. The somatic maturation was a strong predictor of RPA-derived variables in BS. The MPP during all protocol, and the MPP during the Best Set were significant predictable by somatic maturation in both exercises. Mechanical, physiological and perceptual training demands are exercise and maturation dependent.

Thermoregulatory responses to ice slurry ingestion during low and moderate intensity exercises with restrictive heat loss

ObjectivesWe investigated the thermoregulatory responses to ice slurry ingestion during low- and moderate-intensity exercises with restrictive heat loss. DesignRandomised, counterbalanced, cross-over design. MethodsFollowing a familiarisation trial, ten physically active males exercised on a motorised treadmill at low-intensity (L; 40% VO2max) or moderate-intensity (M; 70% VO2max) for 75-min, in four randomised, counterbalanced trials. Throughout the exercise bout, participants donned a raincoat to restrict heat loss. Participants ingested 2gkg−1 body mass of ambient water (L+AMB and M+AMB trials) or ice slurry (L+ICE and M+ICE trials) at 15-min intervals during exercise in environmental conditions of Tdb, 25.1±0.6°C and RH, 63±5%. Heart rate (HR), gastrointestinal temperature (Tgi), mean weighted skin temperature (Tsk), estimated sweat loss, ratings of perceived exertion (RPE) and thermal sensation (RTS) were recorded. ResultsCompared to L+AMB, participants completed L+ICE trials with lower ΔTgi (0.8±0.3°C vs 0.6±0.2°C; p=0.03), mean RPE (10±1 vs 9±1; p=0.03) and estimated sweat loss (0.91±0.2L vs 0.78±0.27L; p=0.04). Contrastingly, Tgi (p=0.22), Tsk (p=0.37), HR (p=0.31), RPE (p=0.38) and sweat loss (p=0.17) were similar between M+AMB and M+ICE trials. RTS was similar during both low-intensity (4.9±0.5 vs 4.7±0.3; p=0.10) and moderate-intensity exercise (5.3±0.47 vs 5.0±0.4; p=0.09). ConclusionsPer-cooling using ice slurry ingestion marginally reduced thermal strain during low-intensity but not during moderate-intensity exercise. Ice slurry may be an effective and practical heat mitigation strategy during low-intensity exercise such as in occupational and military settings, but a greater volume should be considered to ensure its efficacy.

The effect of short-term creatine intake on blood lactic acid and muscle fatigue measured by accelerometer-based tremor response to acute resistance exercise.

[Purpose]The purpose of this study was to investigate the effects of short-term creatine intake on muscle fatigue induced by resistance exercise in healthy adolescent men, i.e., lactic acid concentration and wrist and head tremor measured by an accelerometer.[Methods]Twelve healthy adolescent men who had no experience with creatine intake were included. The subjects were randomly assigned to the creatine group and the placebo group, followed by 5 days of creatine and placebo intake, and 5 times of 5 sets of leg press, leg extension, bench press, and arm curl exercises at 70% repetition maximum (RM). The lactic acid concentration before and after exercising, rate of perceived exertion (RPE), and accelerometer-based wrist tremor and head tremor during exercise were measured. Subsequently, after 7 days to allow for creatine washout, the same exercise treatment and measurement were performed in each group after switching drug and placebo between the groups.[Results]The level of lactic acid before and after the acute resistance exercise trial was significantly lower in the creatine group than in the placebo group (P <0.05). The mean RPE during the resistance exercise was significantly lower in the creatine group than in the placebo group (P <0.05). There was no difference between the two groups in the mean wrist tremor during resistance exercise, but the mean head tremor values were significantly lower in the creatine group than in the placebo group in the arm curl, the last event of the exercise trials (P <0.05).[Conclusion]Short-term creatine intake reduces the blood fatigue factor increased by resistance exercise, and is thought to suppress fatigue, especially in the latter half of resistance exercise. Therefore, these findings indicate that short-term creatine intake can have an improved effect on anaerobic exercise performance.

Comparison of the Affective Responses to Continuous Training and High-Intensity Interval Training Protocols: Application of the Dual-Mode Model.

Alicea, SK, Parrott, AD, Manos, TM, and Kwon, YS. Comparison of the affective responses to continuous training and high-intensity interval training protocols: application of the dual-mode model. J Strength Cond Res 35(11): 3069-3075, 2021-High-intensity interval training (HIIT) is time-efficient and has physiological benefits similar to or greater than that of continuous training (CT); however, there are mixed results regarding how HIIT protocols influence affect. The purpose of this study was to compare acute affective responses between HIIT and CT protocols over time using the Dual-Mode Model (DMM) as a theoretical framework. Subjects included 12 healthy women (aged 19-28 years) who completed a HIIT protocol consisting of a 2-minute work interval (100% V̇o2max) followed by a 2-minute rest interval (∼55% V̇o2max), and a CT protocol set at the workrate corresponding to their respiratory compensation point (RCP; ∼80% V̇o2max). Protocols were matched for average intensity, total duration, and energy expenditure. After blood pressure, anthropometrics, body composition, and V̇o2max measurements were taken, responses were recorded for affect (Feeling Scale [FS]), arousal (Felt Arousal Scale [FAS]), and rate of perceived exertion (RPE) before each protocol, during the last 10 seconds of every 2 minutes during the protocol, and at time points 2, 5, and 10 minutes after the protocol. Heart rate was also monitored continuously, and exercise enjoyment was measured before and after exercise. A repeated-measures analysis of variance revealed no significant differences in affect between CT (M = 2.5, SD = 2.1) and HIIT (M = 2.6, SD = 2.1) protocols over the duration of the exercise. There were no significant differences in mean RPE between CT (M = 12.9, SD = 2.7) and HIIT (M = 13.0, SD = 1.9) protocols (t = 0.333, p = 0.745) or in enjoyment between CT (M = 2.3, SD = 1.1) and HIIT (M = 2.0, SD = 0.9) protocols (t = -0.288, p = 0.492). In addition, based on visual inspection, the general patterning of the mean FS and FAS values between HIIT and CT was similar within the circumplex model, supporting the DMM. In conclusion, a HIIT protocol at V̇o2max and 1:1 exercise:rest interval did not result in a different affect response, perceived exertion, or enjoyment level when compared with a CT protocol at RCP.

Half Soccer Season Induced Physical Conditioning Adaptations in Elite Youth Players.

This study aimed to investigate training-induced fitness changes and their relationship with training-competition load during half a soccer season (18 wks). Training load [heart rate (HR) and ratings of perceived exertion (RPE)] and match time were monitored, including 108 training (3 223 individuals) and 23 match sessions, in 38 youth elite male soccer players. Fitness variables were assessed before and after the study. Yo-Yo intermittent recovery test 1 (Yo-Yo IRT1) improved (P<0.001; 90%CI: 418-632 m; ES: 2.14). Anthropometrical, jump, sprint, and change-of-direction measures remained unchanged. Jump test correlated with sprint (r=0.74; P<0.001; SEE=3.38 m·s-1) and Yo-Yo IRT1 (r=-0.58; P=0.005; SEE=4.11 m) tests. Initial sum of 6 skinfolds was associated with changes in this same measure (r=-0.51; P<0.001; SEE=21%). Initial Yo-Yo IRT1 results were related to changes in Yo-Yo IRT1 (r=-0.84; P<0.001; SEE=10%) and match time played (r=0.44; P=0.033; SEE=445 m). Mean RPE records were related to training spent within 75-90% maximal HR (r=0.54; P<0.001; SEE=4%). The half-season was beneficial for endurance running performance but not for lower-limb strength-velocity production capacity. The more aerobically deconditioned players played fewer minutes of match, although they showed the greatest improvements in endurance performance. Non-soccer-specific, scientifically based, and individualized fitness programs in addition to soccer-specific training are recommended.