Perceived Exertion Research Articles

Breath assessment at with post-tuberculosis patients suffered new coronavirus infection

BACKGROUND: The possibility of mutual aggravation of post-tuberculosis and post-COVID respiratory pathologies requires additional consideration. AIM: To study some subjective breathing parameters at patients with post-tuberculosis pulmonary residual changes after a new coronavirus infection recovering. MATERIALS AND METHODS: The study included two groups: the main group — 14 patients with cured pulmonary tuberculosis, who had recovered from a new coronavirus infection, a comparison group — 52 patients with post-tuberculosis changes non-sick new coronavirus infection who were admitted to the tuberculosis sanatorium “Glukhovskaya” in 2020–2021. The severity of shortness of breath using the Modified Medical Research Council (mMRC) and Borg scales was assessed upon admission to the sanatorium and a month later. Results: The mMRC scale was 1.5 ± 1.4 and 2.1 ± 0.2 and the Borg scale was 1.5 ± 1.4 and 2.9 ± 0.2 before treatment respectively in the main group and the comparison group. According to the mMRC scale initially 14.3 and 11.5% of patients with pulmonary tuberculosis and the comparison group did not complain of shortness of breath and 50% of pulmonary tuberculosis patients and 42.4% of the comparison group defined it as severe. After a month there were 3 or 4 points on the mMRC scale among pulmonary tuberculosis patients. In the comparison group 3-point shortness of breath decreased by 11.2 times most often indicated shortness of breath with 2 score. According to the Borg scale dyspnea was initially assessed as 3 points at 71.5% pulmonary tuberculosis patients. In the comparison group 67.3% patients had grade 3 dyspnea and 11.5% noted 4–6 grade shortness of breath. After a month the proportion of patients with mild shortness of breath at the pulmonary tuberculosis and comparison groups increased by 4.5 and 3.3 times, respectively, and the frequency of 3-grade shortness of breath decreased by 5 and 3.9 times. CONCLUSIONS: Major post-tuberculosis changes, smoking and chronic obstructive pulmonary disease determine the severity of breathing discomfort to a greater extent than the experience of new coronavirus infection but rehabilitation treatment are leveled out these differences. It is advisable to study the state of the respiratory system at patients cured of pulmonary tuberculosis.

Different humidity environments do not affect the subsequent exercise ability of college football players after aerobic high-intensity interval training

Previous studies have explored the effect of differing heat and relative humidity (RH) environments on the performance of multiple anaerobic high-intensity interval training (HIIT). Still, its impact on physiological responses and performance following aerobic HIIT has not been well studied. This study examined the effects of differing RH environments on physiological responses and performance in college football players following HIIT. Twelve college football completed HIIT under four different environmental conditions: (1) 25 °C/20% RH (Control group); (2) 35 °C/20% RH (H20 group); (3) 35 °C/40% RH (H40 group); (4) 35 °C/80% RH (H80 group). The heart rate (HR), mean arterial pressure (MAP), lactate, tympanic temperature (TT), skin temperature (TS), thermal sensation (TS), and rating of perceived exertion (RPE) were recorded continuously throughout the exercise. The heart rate variability (HRV): including root mean squared differences of the standard deviation (RMSSD)、standard deviation differences of the standard deviation (SDNN)、high frequency (HF), low frequency (LF), squat jump height (SJH), cycling time to exhaustion (TTE), and sweat rate (SR) were monitored pre-exercise and post-exercise. The HR, MAP, lactate, TT, Ts, TS, and RPE in the 4 groups showed a trend of rapid increase, then decreased gradually. There was no significant difference in HR, MAP, TT, or RPE between the 4 groups at the same time point (p > 0.05), in addition to this, when compared to the C group, the lactate, Ts, TS in the other 3 groups significant differences were observed at the corresponding time points (p < 0.05). The RMSSD, SDNN, HF, and LF levels in the 4 groups before exercise were not significantly different. The RMSSD and HF in the H40 and H80 groups were significantly decreased and other HRV indicators showed no significant difference after exercise. In sports performance measurement, the SJH and TTE were significantly decreased, but there was no significant difference in the 4 groups. The SR was no significant difference in the 4 groups after exercise. In conclusion, heat and humidity environments elicited generally greater physiological effects compared with the normal environment but did not affect sports performance in college football players.

The Influence of the Playing Surface on Workload Response in Spanish Professional Male Soccer Players.

This study aimed to quantify the influence of the playing surface on workload-related variables (i.e., external load, Rate of perceived exertion (RPE), and mental load) in training sessions with a Spanish professional soccer team. Twenty professional male players from the same soccer team were involved. A total of thirty training sessions related to the preseason period were included. All the players completed training sessions on three playing surfaces: natural turf of poor quality, natural turf of high quality, and third-generation artificial turf. Monitoring during sessions involved assessing internal load (i.e., RPE and mental load) via self-reported questionnaires, and external load using Global Positioning System devices. Linear mixed models showed that RPE was significantly higher on natural turf of high quality than on natural turf of poor quality (p < 0.001). Total distance, relative total distance, the number of accelerations, decelerations, and high metabolic load distance were significantly lower on third-generation artificial turf compared to natural turf of poor quality (p < 0.001) and high quality (p < 0.001). In addition, high-speed running, sprint running distances, and the number of sprints reached higher values on third-generation artificial turf compared to the other two playing surfaces. These findings highlight the need for coaches to consider the type of training surface in soccer to optimize training load planning and prevent injuries.

The Relationship Between the Anaerobic Speed Reserve and Acute Responses to High-Intensity Interval Training in Female Soccer Players.

Aspin, GL, Graham, M, Franklin, J, Hicks, KM, and Taylor, JM. The relationship between the anaerobic speed reserve and acute responses to high-intensity interval training in female soccer players. J Strength Cond Res XX(X): 000-000, 2024-The anaerobic speed reserve (ASR) is a popular method of profiling soccer players, often used to individualize training prescription. This study explored the reliability of ASR profiling, and the relationship between the ASR and acute physiological responses to high-intensity interval training (HIIT). Acute physiological responses to different HIIT types were also compared. Thirteen subelite female soccer players aged 20.2 ± 4.6 years completed 6 exercise sessions. In sessions 1-2, players completed a 40-m sprint to assess maximal sprint speed (MSS) and 1600-m time-trial to estimate maximal aerobic speed (MAS), which were used to calculate ASR and assess test-retest reliability. In sessions 3-6, players completed 4 HIIT sessions (repeated-sprint training, sprint interval training, long intervals, and short intervals HIIT). Intensities for long and short intervals HIIT were individualized according to MAS. Ratings of perceived exertion (RPE), heart rate (HR), and postsession blood lactates were recorded throughout. Relationships between the ASR and acute responses to HIIT, and between HIIT session comparisons in outcome measures were assessed. Anaerobic speed reserve (coefficient of variation ± 95% confidence limits; 3.1 ± 1.5%), MAS (1.8 ± 1.3%), and MSS (0.8 ± 0.6%) indicated acceptable reliability. Moderate correlations between ASR and RPE (r = 0.33), postsession blood lactate (r = 0.34), and HR (r = 0.37) were observed during long intervals HIIT. A strong correlation was observed between ASR and RPE during SIT (r = 0.50). Sprint interval training elicited higher RPE's and postsession blood lactate's than other HIIT sessions. Anaerobic speed reserve has good reliability and may influence acute physiological responses to HIIT in female soccer players.

Follow-up of Cardiopulmonary Responses Using Submaximal Exercise Test in Older Adults with Post-COVID-19.

Data on cardiopulmonary fitness in older adults in the longer term after coronavirus disease 2019 (COVID-19) are of interest as the time required for the full recovery of physical fitness after COVID-19 remains unclear. Some studies have reported that patients do not recover physical fitness for up to 6 or 12 months after COVID-19, whereas other studies have observed full recovery after 12-months. Therefore, this study evaluated and compared the cardiopulmonary responses induced by the 6-minute walk test (6MWT) and 1-minute sit-to-stand-test (STST) results at 3, 6, and 12 months in older adults with and without COVID-19. This study included 59 older adults with and without a history of COVID-19. The cardiopulmonary response parameters including heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse oxygen saturation (O2 sat), rate of perceived exertion (RPE), and leg fatigue were evaluated in the participants after 6MWT and 1-min-STST assessments. Post-COVID-19, older adults showed statistically significant differences in HR, SBP, DBP, O2 sat, RPE, leg fatigue, 6MWT time, and 1-min-STST step numbers at 3, 6, and 12 months (P < 0.001). Moreover, older adults showed statistically significant differences in HR, SBP, DBP, RPE, leg fatigue, O2 sat, and 6MWT distance at 3 months post-COVID-19 compared with those in older adults without COVID-19 (P < 0.001). While older adults showed recovery of cardiopulmonary response parameters according to 6MWT and 1-min-STST findings at the 12-month follow-up post-COVID-19, these results of these measurements did not return to the values observed in older adults without COVID-19.

Effects of Different Caffeine Dosages on Maximal Physical Performance and Potential Side Effects in Low-Consumer Female Athletes: Morning vs. Evening Administration.

While previous studies have explored a range of factors governing the optimal use of caffeine (CAF) in athletes, limited research has explored how time of day (TOD) affects the ergogenic effects of various CAF dosages on physical performance. This study aimed to increase knowledge about how different recommended CAF doses (3 mg/kg vs. 6 mg/kg) ingested at different TODs affected maximal high-intensity physical performance and the perception of potential side effects in female athletes. In this double-blind, randomized, and counterbalanced study, 15 low CAF consumer athletes (aged 18.3 ± 0.5 y) underwent six trials, including three testing conditions assessed across two TODs: one in the morning (08:00 a.m.) and one in the evening (06:00 p.m.). During each condition, the participants ingested either a placebo, 3 mg/kg CAF (CAF (3 mg)), or 6 mg/kg CAF (CAF (6 mg)) capsules 60 min before each test with an in-between washout period of at least 72 h. In each trial, the participants performed a countermovement jumps test (CMJ), a modified agility t test (MATT), a repeated sprint ability (RSA), a rating of perceived exertion (RPE), and finally, a CAF side effects questionnaire. Our findings indicate the absence of an ergogenic effect on CMJ, MAT, and RSA performance in the evening after administering CAF (3 mg) or CAF (6 mg) compared to a placebo. Likewise, when CAF was ingested in the morning, there was an improvement in these performances with both CAF (3 mg) and CAF (6 mg), with greater improvement observed after CAF (6 mg). Additionally, neither the CAF dosage nor the TOD had a significant effect on the RPE. The occurrence of side effects increased significantly after the evening ingestion of CAF, particularly with a moderate dose of CAF (6 mg). Our findings indicate that the effectiveness of CAF depends on the TOD and CAF dosage. When ingested in the morning, a moderate dose of CAF (6 mg), rather than CAF (3 mg), is more effective in improving short-term physical performance without affecting CAF side effects in female athletes. Nevertheless, when ingested in the evening, neither dose was sufficient to enhance short-term physical performance, and both dosages increased the incidence of CAF side effects, particularly at a moderate dose.

Influence of sustained mild dehydration on thermoregulatory and cognitive functions during prolonged moderate exercise

PurposeThe current study investigated whether sustained mild dehydration affects thermoregulatory function and cognitive performance during prolonged exercise.MethodsTwelve young adults performed a test consisting of three sets of 20-min exercise with 2-min intervals under euhydrated (control, CON) and mildly dehydrated conditions (MDEH) at an ambient temperature of 30 °C and 60% relative humidity. MDEH was established by restricting water intake for 24 h, resulting in urine specific gravity of ≥ 1.020. Heart rate (HR), mean arterial blood pressure (MAP), skin blood flow (SkBF), sweat rate (SR) on the chest and forearm, and ear canal and mean skin surface temperatures (Tear and mean Tskin, respectively) were continuously recorded. For each exercise set, thermal and humid sensations and thermal discomfort were assessed using visual analog scales (VAS), and the rating of perceived exertion (RPE) was estimated. Cognitive performance on the Go/No-Go (easy) and incongruent Stroop (difficult) tasks was assessed before and after the test.ResultsNo differences were observed in HR, MAP, SkBF, SR, Tear, and mean Tskin between the CON and MDEH. Thermal and humidity sensations, thermal discomfort, and RPE were higher in MDEH than in CON. Moreover, response time to the Stroop task was prolonged in MDEH.ConclusionThese findings suggest that sustained mild dehydration does not affect autonomic thermoregulation during exercise. Augmented thermal perception and perceived exertion, which are necessary for behavioral thermoregulation, were noted; however, cognitive function may be attenuated under MDEH.

How strenuous is esports? Perceived physical exertion and physical state during competitive video gaming.

Esports or competitive video gaming is a rapidly growing sector and an integral part of today's (youth) culture. Esports athletes are exposed to a variety of burdens, that can potentially impact an athlete's health and performance. Therefore, it is important that esports athletes are aware of (physical) burden and exertion associated with esports. For this purpose, a study was conducted to evaluate the influence of competitive video gaming on the perceived physical exertion and the perceived physical state (PEPS). Thirty-two healthy male esports athletes participated in two competitive video gaming sessions lasting 90-120 min, interrupted by a 10-minute passive sitting break. Repeated measures of perceived physical exertion (Borg Categorial Ratio-10 scale) and perceived physical state were recorded before, during, and after each video game session. Repeated measures ANOVA and Friedman's test were used for statistical analysis. The results showed a significant difference in all dimensions of the PEPS (p < 0.05) as well as in Borg scale (p < 0.001). Post-hoc tests revealed significant increases in Borg scale between baseline measurements (T0: 1.0 ± 1.0) and after the first competitive video gaming session (T1: 2.4 ± 1.3, p < 0.001), as well as after the second competitive video gaming session (T3: 3.0 ± 1.7, p < 0.001). Furthermore, there was a significant reduction in perceived exertion between the measurement time after the first competitive video gaming session (T1) and the break (T2: 1.3 ± 1.2, p < 0.001). The PEPS dimensions activation, trained, and mobility showed similar significant changes in post-hoc analysis. The results indicate that the perceived physical burden significantly increases during esports participation. As the duration of competitive video gaming extends, the perceived physical state decreases and perceived physical exertion increases. A passive break between two video game sessions can at least partially restore physical exertion and physical state. However, this break neither returns the scores to their baseline levels nor prevents a further decline in scores during the second video game session. Over time and with a lack of observation, this could result in health and performance limitations.

Predicting one repetition maximum in novice males: An RPE-based bench press model

This study aimed to estimate one repetition maximum (1RM) of healthy males based on the Rating of Perceived Exertion (RPE) in bench press movement and to provide a particular predictive equation. Seventy healthy males (Age: 24.93 ± 0.64 years; BMI: 25.04 ± 0.35 kg/m2) with no previous experience of resistance training performed 1RM of bench press with closed eyes and then chose a number to determine the intensity by RPE scale of 1–10 (CR1-10 scale). The intensity of this repetition was randomly selected based on the percentages of 1RM: 60%, 65%, 70%, 75%, 80%, 85%, 90% and 95%. A special prediction equation was provided based on a mathematical model using the weight lifted, RPE, and RPE coefficient. Moreover, the standardized testing protocol of 1RM (STP) and Brzycki equation protocol (BEP) were used to verify the validity of the RPE equation. Predictive equations were produced and cross-validated using repeated k-fold cross-validation by stepwise multiple linear regression. BEP and STP did not differ significantly from RPE-equation in predicting 1RM (p > 0.05). Based on the BEP and STP, a 1RM attempt for inexperienced males resulted in 74.20 ± 2.24 kg and 77.47 ± 2.17, respectively, while the RPE equation produced 77.86 ± 2.58 kg. There were significant results for linear regression (p = 0.001). Pearson correlation coefficients between BEP and STP with predicted 1RM were 0.99. The new method of 1RM based on RPE performed well in 1RM performance in inexperienced males, and it appeared safe, accurate, and time-effective.

Firefighters' muscle activity change during firefighting training program.

Research on muscle activity to reduce injuries during firefighting training has getting increasing attention. The purpose of this study was to assess the activity changes in nine muscles of firefighters during the seven firefighting training programs, and to analyze the influence of different firefighting training programs on muscle activity. Ten healthy male firefighters were recruited to measure the field surface electromyographic activities (including the percentage of Maximum Voluntary Contraction electromyography (% MVC) and the integrated electromyography value (iEMG)) during all the firefighting training programs. The results showed that the electromyographic activity of gastrocnemius (GA) was stronger in climbing the hooked ladder and climbing the six-meter long ladder training programs. Arms, shoulders, and lower limb muscles were more activated, myoelectric activities were more intense, and fatigue in these areas was more likely to occur during climbing five-story building with loads. Compared with other muscles, erector spine (ES) had a higher degree of activation during different postures of water shooting. The Borg scale scores of shoulders, trunk, thighs and calves were also higher. After completing all training programs, GA, tibialis anterior (TA), trapezius (TR), and ES were strongly activated, and all muscles had obvious force. The % MVC and iEMG analyses correspond well with the Borg Scale score. The results can provide certain reference for reducing the musculoskeletal injury of firefighters, carrying out scientific training and formulating effective injury prevention measures for them.

EFFECTS OF SHORT-TERM PRACTICE OF FAST DEEP BREATHING EXERCISE ON PARASYMPATHETIC FUNCTIONS IN TRANS-FEMORAL AND TRANS-TIBIAL-AMPUTATION PATIENTS

Background of the Study: After lower limb amputation, the functioning parasympathetic system is compromised so the regular practice of breathing techniques improves cardiorespiratory functions. To determine the effects of short-term fast-breathing exercises on parasympathetic functions in amputees. Methodology: The study was conducted at the Armed Forces Institute of Rehabilitation Medicine Rawalpindi, on 61 stable transfemoral and transtibial amputation patients within the duration of six months (January to June 2017), performed fast deep breathing exercises Parasympathetic functions were observed through different variables. Data was analyzed using IBM® SPSS® v 21. Results: Breathing exercises showed significant effects on HR with a p-value of (0.000), the Valsalva ratio had a p-value of (0.000), and oxygen saturation was improved in both control and experimental groups with p-values of (0.000) and (0.000). Valsalva’s BP systolic and diastolic p values were (0.001) (0.012), breathing exercise BP systolic and diastolic values were (0.16) and (0.000), and orthostatic testing BP systolic and diastolic p values were (0.134) and (0.389). Post Borg scale readings showed a significant decrease in exertion level Conclusion: The study concludes that short-term fast deep breathing exercise improves cardiovagal functioning.

The effect of post-match fatigue on physical performance in adolescent soccer players.

Soccer involves many physically challenging actions and engaging in such activities can induce a decline in performance due to physical fatigue which predisposes players to develop injuries. The present study aimed to examine the impact of post-match fatigue on functional performance and Inter-Limb Asymmetry Index (LSI) in adolescent soccer players. Thirty-eight adolescent male soccer players (15-18 years) completed a battery of functional performance measures (Rate of Perceived Exertion (RPE) scale, 10 m sprint, agility T-test, and Single leg hop for distance (SLHD) test). The data collection started prior to a soccer match and consisted of two testing sessions; two hours before the match, while the subsequent testing session was performed within two hours immediately following the match. The study results revealed a significant effect of post-match fatigue on change of direction abilities and SLHD (moderate effect size). However, no significant differences were observed in the 10 m sprint test and LSI (P>0.05). Functional performance measures such as agility test and SLHD test can detect physical ability changes due to post-match fatigue in adolescent soccer players. The study findings offer insightful and practical information on the importance of employing field-based functional performance measures in monitoring players' recovery following a game.

Influence of compression garments on perceived exertion during maximal isometric exercises

Compression garments have gained popularity in the sports world as a means to enhance athletic performance and accelerate recovery. This study investigates the effectiveness of upper-body compression garments and their impact on the rate of perceived exertion (RPE) during maximal isometric contractions. Eight adult males, students of a Master's degree program in Sports Sciences, participated in the study, conducting tests in controlled conditions at the University of Salerno. The subjects performed maximal isometric contractions in three separate sessions, wearing compression garments (CG), traditional sportswear (noCG), and a tight-fitting garment without compression effect, to minimize the placebo effect (Placebo), respectively. Perceived exertion was assessed using the modified CR-10 scale. Statistical analysis revealed a significant reduction in RPE when athletes wore compression garments compared to other conditions, suggesting a benefit in the use of such clothing. The findings indicate that compression garments can attenuate the perception of exertion during intense physical activities, with potential implications for performance, comfort, and recovery. This study contributes to the existing literature by expanding the understanding of the effects of compression clothing and highlighting the importance of further research to optimize the use of these garments in enhancing athletic performance.

Impact of Transcranial Direct Current Stimulation on the Capacity to Perform Burpees: A Randomized Controlled Trial

Transcranial direct current stimulation (tDCS) has emerged as a potential intervention to improve physical performance. This study investigates the effects of tDCS applied to the primary motor cortex (M1) and dorsolateral prefrontal cortex (DLPFC) on performance in a maximal effort task, specifically the No-Jump Burpee exercise. Twenty healthy male subjects (26.0 ± 4.91 years) completed three experimental conditions (a-DLPFC, a-M1, and SHAM) in a double-blind crossover design. Prior to the performance of burpees to exhaustion, tDCS (2 mA, 20 min) was administered. The total number of repetitions, vastus lateralis muscle oxygen saturation, heart rate, and subjective perception of exertion (RPE) during exercise were measured. Repeated ANOVAs showed a significant effect of condition on the number of repetitions (p &lt; 0.001). Subjects performed more repetitions under the M1 condition (68 ± 19.5) compared to DLPFC (63 ± 17.9) and SHAM (58 ± 18.0), with significant differences between all conditions. This study demonstrates that tDCS can improve performance in a physical endurance task such as the No-Jump Burpee. The findings suggest that tDCS may be a viable ergogenic tool for improving athletic performance. Future research should explore the underlying mechanisms and the practical application of these results in long-term physical training programs (NCT06472882).

The Effect of Assistive Robotic Technologies on Quality of Life and Functional Independence in Individuals with Spinal Cord Injury

Purpose: To investigate the effect of assistive robotic technologies on quality of life, functional independence, and perceived fatigue level during exertion in individuals with spinal cord injury. Method: This research involved a cohort of 25 patients who had been diagnosed with spinal cord injury (SCI). To assess their progress, clinical assessments were administered both at the commencement and completion of a six-week treatment regimen. The evaluations encompassed the use of the Spinal Cord Independence Measure (SCIM III) to measure their performance in daily living activities and mobility. Additionally, the quality of life was assessed using the World Health Organization Quality of Life Scale – Short Form (WHOQOL-BREF) scale, while the levels of fatigue experienced during rehabilitation were gauged using the Modified Borg Scale (RPE). Results: The participants' average age and BMI were 40.72±1.28 and 23.43±0.57. Statistically significant differences were found in self-care (p=0.006) and mobility (p=0.004) values of SCIM III scale compared to pretreatment values. WHOQOL-BREF General health status, Physical health, Psychological, Social relations and Environment sub-parameters all showed statistically significant differences compared to pre-treatment values (p=0.001). There was a significant decrease in the RPE value to determine the level of fatigue during exertion in robotic walking training (p

Increased Neuromuscular Activity, Force Output, and Resistance Exercise Volume When Using 5-Minute Compared with 2-Minute Rest Intervals Between the Sets.

McMahon, G, Best, N, Coulter, T, and Erskine, RM. Increased neuromuscular activation, force output and resistance exercise volume when using 5-minute compared with 2-minute rest intervals between the sets. J Strength Cond Res 38(9): 1527-1534, 2024-Longer rest intervals between resistance exercise (RE) sets may promote greater muscle hypertrophy and strength gains over time by facilitating the completion of greater training volume and intensity. However, little is known about the acute neuromuscular responses to RE sets incorporating longer vs. shorter rest intervals. Using a within-subject, crossover design, 8 healthy, young subjects completed 2 separate acute bouts of 4 sets of 8 × 3-s maximal isometric contractions using either a 2-minute (REST-2) or 5-minute (REST-5) rest interval between sets. Peak torque (PT) and electromyography (EMG) were measured pre and 5 minutes postexercise. Peak torque and mean torque (MT), EMG, mean, and median frequencies were measured during each set, whereas blood lactate (BLa), heart rate (HR), and rating of perceived exertion (RPE) were measured following each set. Peak torque and MT were lower ( p < 0.05) in sets 3 and 4, and sets 2-4 in REST-2 compared with REST-5, respectively. Electromyography and BL were lower and higher, respectively, in REST-2 vs. REST-5. There was no main effect of condition on HR or RPE. Pre-to-post exercise reductions in PT (-17 ± 9% vs. -4 ± 7%) and EMG (-29 ± 14% vs. -10 ± 7%) were greater ( p < 0.001) in REST-2 vs. REST-5. Total exercise volume was less in REST-2 vs. REST-5 (9,748 ± 2296 N·m -1 vs. 11,212 ± 2513 N·m -1 , p < 0.001). These results suggest that incorporating 5-minute between-set rest intervals into a resistance exercise session facilitates improved neuromuscular function, increased exercise volume, and less metabolic stress compared with 2-minute rest intervals. Thus, 5-minute rest intervals may be more efficacious for promoting muscle hypertrophy and strength gains in a chronic resistance training program.

Consistency between the ACGIH TLV for hand activity and proposed action levels for wrist velocity and forearm muscular load based on objective measurements: an example from the assembly industry

Objectives. This study aimed to investigate the consistency between results of the American Conference for Governmental Occupational Hygienists (ACGIH) threshold limit value (TLV) for hand activity and proposed action levels of objective measurements in risk assessments of work-related musculoskeletal disorders. Methods. Wrist velocities and forearm muscular load were measured for 11 assemblers during one working day. Simultaneously, each assembler’s hand activity level (HAL) during three sub-cycles was rated twice on two separate occasions by two experts, using a HAL scale. Arm/hand exertion was also rated by the assemblers themselves using a Borg scale. In total, 66 sub-cycles were assessed and assigned to three exposure categories: A) below ACGIH action limit (AL) (green); B) between AL and TLV (yellow); and C) above TLV (red). The median wrist velocity and the 90th percentile of forearm muscular load obtained from the objective measurements corresponding to the sub-cycles were calculated and assigned to two exposure categories: A) below or C) above the proposed action level. Results. The agreement between ACGIH TLV for hand activity and the proposed action level for wrist velocity was 87%. Conclusions. The proposed action level for wrist velocity is highly consistent with the TLV. Additional studies are needed to confirm the results.

Sex-Related Glycemic and Cardiovascular Responses After Continuous and Interval Aerobic Sessions in Patients With Type 1 Diabetes: A Randomized Crossover Study

We aimed to investigate sex-related glycemic and cardiovascular responses after intensity- (moderate) and duration- (30 minutes) matched interval aerobic exercise (IAE) and continuous (CAE) aerobic exercise sessions in patients with type 1 diabetes mellitus (T1DM). A total of 19 volunteers (10 women) participated in 2 randomized and crossover sessions (1:1). Heart rate, systolic and diastolic blood pressure, double product, and blood glucose (BG) levels were measured before (PRE), immediately after (POST-0), and 20 minutes after (POST-20) each session. The rates of perceived exertion (RPE) and enjoyment levels (ELs) were assessed after each session. Generalized estimating equations were used to analyze the data (condition × time × sex). Regarding sex-related changes, men showed BG reductions at POST-0 and POST-20 after CAE (∆: -3.7 and -3.7 mmol/L, respectively) and only at POST-0 after IAE (∆: -1.6 mmol/L), with 1 episode of hypoglycemia occurring in the latter group. In contrast, women showed reduced BG values only after CAE at both time points (∆: -1.4 and -1.7 mmol/L) compared with PRE values. The decrease in BG levels at both time points was higher for men after CAE than IAE. Cardiovascular responses, RPEs, and ELs were similar between exercise sessions, except for blood pressure, which showed higher values in men. In conclusion, lower BG levels were observed after CAE, with greater reductions in men. Similar cardiovascular, RPE, and EL responses were found across sexes and sessions. Consideration of sex-specific recommendations may be warranted when prescribing aerobic exercise, particularly, for men with irregular physical activity levels.

Influence of the Number of Players on the Load of Soccer Players During Transition Games.

The aims of this study were to determine the effect of different compositions in transition games (TGs) on the load of soccer players and to evaluate their performance in physical tests. Using a GPS system, 18 players were monitored during: 3vs2, 2vs1 and 1vs1. Distance covered (DC), DC 18-20.9 km·h-1, 21-23.9 km·h-1,>24 km·h-1, peak speed, accelerations (Acc) and decelerations (Dec)>1.0 m·s-2 and>2.5 m·s-2 and rate of perceived exertion (RPE) were recorded. Before and after each TG, countermovement-jump (CMJ), 15- (S15) and 30 m (S30) speed tests were assessed. TG3vs2 showed greater DC and Dec>1.0 m·s-2 than TG2vs1, and DC, DC 18.0-23.9 km·h-1, Acc>1.0 m·s-2 and Dec>2.5 m·s-2 than TG1vs1 (p<0.01). TG2vs1 achieved higher DC, DC 18.0-23.9 km·h-1, and Acc>2.5 m·s-2 (p<0.01) but lower peak speed (p=0.02) and RPE (p=0.02) than TG1vs1. Post-intervention, TG1vs1 showed lower CMJ and higher S15 (p=0.02), while TG3vs2, showed improvements in CMJ (p<0.01). The three tasks showed large variations for DC>24 km·h-1, Acc>1.0 m·s-2, Dec>1.0 m·s-2 and Dec>2.5 m·s-2. The load of TGs is sensitive to their player composition.

Perturbation-based Balance Training in Adults Aged Above 55 Years with Chronic Low Back Pain: A Comparison of Effects of Water versus Land Medium - A Preliminary Randomized Trial.

'Rapid balance reaction' or 'perturbation' training is an emerging paradigm in elderly back pain rehabilitation due to its connection to postural stability. This study aimed to inform the feasibility and practicality of perturbation-based balance training (PBT) using a stratification approach and to determine the effectiveness of land versus water-based PBT in elderly individuals with chronic low back pain (CLBP). Elderly CLBP participants (n=24) received exercise interventions as per treatmentbased classification (TBC) and were randomly allotted into water-based perturbation exercises (WBPE, Mean age=63.0±2.6years, n=12) and land-based perturbation exercise group (LBPE, 62.3±2.6 years, n=12). Pain intensity, disability, scores of fear-avoidance beliefs, fall efficacy, and rate of perceived exertion (RPE) were assessed before and at the end of 6 weeks. WBPE group reported a significant reduction in pain score (median difference(MD)):2, p<0.03), fear avoidance behaviour for work (MD:9, p<0.01) and fear avoidance behaviour for physical activity (MD:10, p< 0.05), improved straight leg raise right (SLR) (MD:37.5°, p<0.05), and improved modified fall efficacy scores (MFES, MD:25, p<0.05) compared to the LBPE group at post-intervention. Within-group analysis in both groups revealed significant improvement in clinical outcomes except for fear-avoidance beliefs related to physical activity in the LBPE group. Subgroup analysis revealed that the high BMI elderly CLBP group of LBPE had significant improvements similar to the WBPE group except for scores of FABQ physical activity scores and SLR. Possible key factors for future research are discussed in the realms of perturbation exercise in the elderly with CLBP.