Do Men and Women Differ in Hematological Adaptations to 24 Weeks of Crossfit® Training?

Regular exercise can modulate the immune system functioning through changes in the number and function of leukocytes as well as in red blood cells and other typical blood markers. High intensity exercise promotes increases in cytotoxic activity, phagocytic capacity, chemotaxis and cell apoptosis. The aim of the study was to compare the chronic effects of a 24-week training program using CrossFit® methodology on hematological variables of men vs. women. Twenty-nine CrossFit® athletes (35.3 ± 10.4 years, 175.0 ± 9.2 cm, 79.5 ± 16.4 kg) participated in the study. The blood count, the lipid profile and glucose markers were measured every two months during the study period. The erythrocyte count and hemoglobin concentrations increased in months 4 and 6 in men and women, respectively. Hematocrit levels increased in men in months 2, 4 and 6, while in women only in month 6. Red cell distribution width increased in men in month 6 when compared to the value in month 2. Segmented neutrophils increased in men in month 6 and eosinophil levels increased in women in month 6. Differences between the two sexes were observed in monocytes levels at baseline, as well as in months 2, 4 and 6. Cross-Fit® training increased red cell count indicators in both sexes, which may be related to increased erythropoiesis. Some white blood cell counts were altered and these differed between sexes. The number of lymphocytes remained stable throughout the experiment.

Acute Responses in Blood Flow Restriction Low-intensity Aerobic Training: A Meta-analysis.

The purpose was to determine the effect low-intensity training with blood flow restriction (LI-BFR) versus high-intensity aerobic training (HIT) on acute physiological and perceptual responses. The Cumulative Index to Nursing and Allied Health Literature, National Library of Medicine, Scopus, SPORTDiscus and Web of Science databases and the reference list of eligible studies were consulted to identify randomized experimental studies, published until July 4, 2022, that analyzed physiological or perceptual responses between LI-BFR versus HIT in healthy young individuals. Mean difference (MD) and standardized mean difference (SMD) were used as effect estimates and random effects models were applied in all analyses. Twelve studies were included in this review. During exercise sessions, HIT promoted higher values of heart rate (MD=28.9 bpm; p<0.00001; I 2 =79%), oxygen consumption (SMD=4.01; p<0.00001; I 2 =83%), ventilation (MD=48.03 l/min; p=0.0001; I 2 =97%), effort (SMD=1.54; p=0.003; I 2 =90%) and blood lactate (MD=3.85 mmol/L; p=0.002; I 2 =97%). Perception of pain/discomfort was lower in HIT (SMD=-1.71; p=0.04; I 2 =77.5%). In conclusion, LI-BFR promotes less pronounced physiological responses than HIT but with greater perception of pain.

Force-velocity relationship in Paralympic powerlifting: two or multiple-point methods to determine a maximum repetition.

BACKGROUND: Due to the absence of evidence in the literature on Paralympic Powerlifting the present study investigated various methods to assess bench press maximum repetition and the way each method influences the measurement of minimum velocity limit (MVT), load at zero velocity (LD0), and force-velocity (FV). OBJECTIVE: To evaluate the precision of the multi-point method using proximal loads (40, 50, 60, 70, 80, and 90% of one repetition maximum; 1RM) compared to the four-point method (50, 60, 70, and 80% of 1RM) and the two-point method using distant loads (40 and 80% and 50 and 80% of 1RM) in in the MVT, LD0, and FV, in bench press performed by Paralympic Powerlifters (PP). METHODS: To accomplish this, 15 male elite PP athletes participated in the study (age: 27.7 ± 5.7 years; BM: 74.0 ± 19.5 kg). All participants performed an adapted bench press test (free weight) with 6 loads (40, 50, 60, 70, 80, and 90% 1RM), 4 loads (50, 60, 70, and 80% 1RM), and 2 loads (40-80% and 50-80% 1RM). The 1RM predictions were made by MVT, LD0, and FV. RESULTS: The main results indicated that the multiple (4 and 6) pointsmethod provides good results in the MVT (R2 = 0.482), the LD0 (R2 = 0.614), and the FV (R2 = 0.508). The two-point method (50-80%) showed a higher mean in MVT [1268.2 ± 502.0 N; ICC95% 0.76 (0.31-0.92)], in LD0 [1504.1 ± 597.3 N; 0.63 (0.17-0.86)], and in FV [1479.2 ± 636.0 N; 0.60 (0.10-0.86)]. CONCLUSION: The multiple-point method (4 and 6 points) and the two-point method (40-80%) using the MVT, LD0, and FV all showed a good ability to predict bench press 1RM in PP.

Psychophysiological effects of different execution speeds of single bout exercise in outdoor fitness equipment performed by older men

Abstract Aims: This study aimed to investigate the effects of different cadences of movement in ATI equipment on the psychophysiological parameters of older adults during the training session. Methods: Fifteen physically independent older men voluntarily participated in this study. Three 30-min exercise sessions were randomly distributed (5 min warm-up, 20 min exercise, 5 min cooldown), comprising exercises with different cadences low (L: 1 movement every 4 s), medium (M: 1 movement every 2 s), and high cadence (H: 1 movement per second); all with 30" of stimulus and 30" recovery using the following devices: elliptical, rower, surf/elliptical and leg press. Heart rate (HR), rate of perceived exertion (RPE), rate of perceived recovery (RPR), and feeling scale (FS) were evaluated before and immediately after the three sessions. The difference between moments was analyzed by analysis of variance with a significance level of p < 0.0001). Results: Cadence L (56 ± 2 %) showed lower values of relative HR than M (70 ± 5%) and H (85 ± 5%), which also differed from each other. Significant differences (p < 0.01) for the area under the curve of RPE (L: 75 ± 26, M: 115 ± 16, H: 154 ± 4) and RPR (L: 173 ± 16, M: 139 ± 12, H: 97 ± 6; UA) were identified among the cadences. Statistical differences (p < 0.01) were found on RPE 30 min of the session (L: 4.2 ± 0.7 < M: 5.7 ± 0.7 < H: 7.4 ± 0.5). Conclusion: The performance of different cadences induced different psychophysiological responses in older adults undergoing exercise sessions in the ATI. The moderate cadence provided an increase in HR with values considered safe for the exercise and therefore can be recommended for this population when using this equipment.

Energy expenditure in hiit whole body associated with electromyostimulation / Gasto energético en hiit con peso corporal asociado a electroestimulación / Gasto energético no hiit com peso do corpo associado à eletromioestimulação

ABSTRACT Introduction: The use of whole body electromyostimulation (WB-EMS) has been shown to be an efficient method for inducing significant improvements in muscle strength and performance outcomes. Hypothetically, WB-EMS had been considered an enhancer of energy expenditure in the session, but this remains unclear. Objective: In view of the lack of information, this study aims to evaluate the energy expenditure of WB-EMS associated with whole body High-Intensity Interval Training (HIIT). Methods: Fourteen male participants were submitted into two randomized exercise sessions: HIIT (whole body weight exercises without WB-EMS) and HIIT+WB-EMS (whole body weight exercises associated with WB-EMS). For both exercise conditions, the subjects performed whole body HIIT according to the following protocol: 3 minutes of warm-up followed by 4 exercises (30 seconds of stimulus) organized in 2 blocks, with 3 sets in each exercise, a rest period of 15 seconds between sets, and 180 seconds between blocks. The following exercises were performed: jumping jacks, squat and thrusts, burpees, and spider plank. Results: Significant differences were found in the absolute VO2 (HIIT:2.18±0.34, HIIT+WB-EMS:2.32±0.36 L.min−1) and relative VO2 (HIIT:26.30±3.77, HIIT+WB-EMS:28.02± 3.74 ml.kg.min−1), MET (HIIT:7.51±1.07, HIIT+WB-EMS:8.00±1.07), lactate concentration (HIIT:11.59±2.16, HIIT+WB-EMS: 12.64±1.99 mmol.L−1) and total energy expenditure (HIIT: 249.6± 45.04 Kcal, HIIT+ WB-EMS: 268.9±40.67 Kcal; 7.46 ± 5.31%). Conclusion: Our data indicate that the use of WB-EMS associated with HIIT generated a slightly higher metabolic demand than that of the control. However, the absolute differences do not allow us to indicate the superiority of WB-EMS, and future trials should be designed to determine the long-term effects.

RESUMEN Introducción: Se ha demostrado que el uso de la electroestimulación de cuerpo entero (WB-EMS) es un método eficaz para inducir mejoras significativas en la fuerza muscular y los resultados de rendimiento. Hipotéticamente, la práctica de WB-EMS se consideró un potenciador del gasto calórico en la sesión, pero esto aún no está claro. Objetivo: el objetivo del estudio fue evaluar el gasto energético del WB-EMS asociado al HIIT con el peso corporal. Métodos: Se asignaron al azar catorce participantes masculinos a dos sesiones de ejercicio: HIIT (ejercicios de peso corporal total sin WB-EMS) y HIIT + WB-EMS (ejercicios de peso corporal total asociados con WB-EMS). Para ambas condiciones de ejercicio, los sujetos realizaron HIIT con peso corporal según el siguiente protocolo: 3 minutos de calentamiento seguido de 4 ejercicios (30 segundos de estímulo) organizados en 2 bloques con 3 series en cada ejercicio y 15 segundos entre series y ejercicios y 180 segundos entre bloques de descanso pasivo con los siguientes ejercicios realizados: jump jack, squat and thrust, burpee y spider plank. Resultados: Se encontraron diferencias significativas en el consumo de VO2 absoluto (HIIT: 2,18 ± 0,34, HIIT + WB-EMS: 2,32 ± 0,36 L.min−1) y relativo (HIIT: 26,30 ± 3,77, HIIT + WB-EMS: 28,02 ± 3,74 ml.kg.min1), MET (HIIT: 7,51 ± 1,07, HIIT + WB-EMS: 8,00 ± 1, 07), concentración de lactato (HIIT: 11,59 ± 2,16, HIIT + WB-EMS: 12,64 ± 1,99 mmol.L−1) y gasto energetico total (HIIT: 231,5±36,38Kcal, HIIT + WB-EMS:246,9± 38,76Kcal; 6,14± 5,61%). Conclusión: Nuestros datos indican que el uso de WB-EMS asociado a HIIT generó, en una de manera sutil, una mayor respuesta a la demanda metabólica que la situación de control. Sin embargo, las diferencias absolutas no permiten indicar la superioridad del WB-EMS con estudios futuros y deben planificarse.

RESUMO Introdução: O uso da eletromioestimulação de corpo inteiro (whole body electromyostimulation - WB-EMS) tem mostrado ser um método eficiente para induzir melhora significativa da força muscular e do desempenho. Hipoteticamente, a prática de WB-EMS foi considerada potencializadora do gasto energético na sessão, mas isso ainda não está claro. Objetivo: Diante da escassez de informações, o objetivo deste estudo foi avaliar o gasto energético da WB-EMS associada ao treinamento intervalado de alta intensidade (HIIT) com o peso corporal. Métodos: Quatorze participantes do sexo masculino foram submetidos a duas sessões de exercícios randomizadas: HIIT (exercícios com peso corporal sem WB-EMS) e HIIT + WB-EMS (exercícios com peso corporal associados a WB-EMS). Para ambas as condições de exercício, os indivíduos realizaram HIIT com peso corporal, de acordo com o seguinte protocolo: 3 minutos de aquecimento seguidos de 4 exercícios (30 segundos de estímulo), organizados em 2 blocos com 3 séries em cada exercício, com 15 segundos de descanso passivo entre as séries e 180 segundos entre os blocos, com os seguintes exercícios realizados: jumping jack (polichinelo), squat and thrust, burpee e spider plank. Resultados: Diferenças significativas foram encontradas no consumo de VO2 absoluto (HIIT: 2,18 ± 0,34, HIIT + WB-EMS: 2,32 ± 0,36; L.min−1) e VO2 relativo (HIIT: 26,30 ± 3,77, HIIT + WB-EMS: 28,02 ± 3,74; ml.kg.min−1), MET (HIIT: 7,51 ± 1,07, HIIT + WB-EMS: 8,00 ± 1,07), concentração no sangue de lactato (HIIT: 11,59 ± 2,16, HIIT + WB- EMS: 12,64 ± 1,99 mmol.L−1) e gasto energético total (HIIT: 249,6± 45,04 Kcal, HIIT+ WB-EMS: 268,9± 40,67 Kcal; 7,46 ± 5,31%). Conclusão: Nossos dados indicam que o uso de WB-EMS associado ao HIIT gerou demanda metabólica ligeiramente superior à do controle. Entretanto, as diferenças absolutas não permitem indicar superioridade do WB-EMS, e estudos futuros devem ser planejados de modo a determinar os efeitos a longo prazo. Nível de evidência II.

Performance Prediction Equation for 2000 m Youth Indoor Rowing Using a 100 m Maximal Test.

BACKGROUND: The exhaustive series of tests undergone by young athletes of Olympic rowing prior to important competitions imply loads of physical stress that can ultimately impact on mood and motivation, with negative consequences for their training and performance. Thus, it is necessary to develop a tool that uses only the performance of short distances but is highly predictive, offering a time expectancy with high reliability. Such a test must use variables that are easy to collect with high practical applicability in the daily routine of coaches. OBJECTIVE: The objective of the present study was to develop a mathematical model capable of predicting 2000 m rowing performance from a maximum effort 100 m indoor rowing ergometer (IRE) test in young rowers. METHODS: The sample consisted of 12 male rowing athletes in the junior category (15.9 ± 1.0 years). A 100 m time trial was performed on the IRE, followed by a 2000 m time trial 24-h later. RESULTS: The 2000 m mathematical model to predict performance in minutes based on the maximum 100 m test demonstrated a high correlation (r = 0.734; p = 0.006), strong reliability index (ICC: 0.978; IC95%: [0.960; 0.980]; p = 0.001) and was within usable agreement limits (Bland -Altman Agreement: -0.60 to 0.60; 95% CI [-0.65; 0.67]). CONCLUSION: The mathematical model developed to predict 2000 m performance is effective and has a statistically significant reliability index while being easy to implement with low cost.

Evaluation of the Post-Training Hypotensor Effect in Paralympic and Conventional Powerlifting.

High blood pressure (HBP) has been associated with several complications and causes of death. The objective of the study was to analyze the hemodynamic responses in Paralympic bench press powerlifting (PP) and conventional powerlifting (CP) before and after training and up to 60 minutes (min) after training. Ten PP and 10 CP athletes performed five sets of five repetition maximal bench press exercises, and we evaluated systolic, diastolic, and mean blood pressure (SBP, DBP, and MBP, respectively), heart rate (HR), heart pressure product (HPP), and myocardial oxygen volume (MVO2). The SBP increased after training (p < 0.001), and there were differences in the post training and 30, 40, and 60 min later (p = 0.021), between 10 and 40 min after training (p = 0.031, η2p = 0.570), and between CP and PP (p =0.028, η2p = 0.570). In the MBP, there were differences between before and after (p = 0.016) and 40 min later (p = 0.040, η2p = 0.309). In the HR, there was a difference between before and after, and 5 and 10 min later (p = 0.002), and between after and 10, 20, 30, 40, 50, and 60 min later (p < 0.001, η2p = 0.767). In HPP and MVO2, there were differences between before and after (p = 0.006), and between after and 5, 10, 20, 30, 40, 50, and 60 min later (p < 0.001, η2p = 0.816). In CP and PP, there is no risk of hemodynamic overload to athletes, considering the results of the HPP, and training promotes a moderate hypotensive effect, with blood pressure adaptation after and 60 min after exercise.

Force production and muscle activation during partial vs. full range of motion in Paralympic Powerlifting.

Paralympic Powerlifting is a sport in which the strength of the upper limbs is assessed through bench press performance in an adapted specific bench. It is therefore essential to optimize training methods to maximize this performance. The aim of the present study was to compare force production and muscle activation involved in partial vs. full range of motion (ROM) training in Paralympic Powerlifting. Twelve male athletes of elite national level in Paralympic Powerlifting participated in the study (28.60 ± 7.60 years of age, 71.80 ± 17.90 kg of body mass). The athletes performed five sets of 5RM (repetition maximum), either with 90% of 1RM in full ROM or with a load of 130% 1RM in partial ROM. All subjects underwent both exercise conditions in consecutive weeks. Order assignment in the first week was random and counterbalanced. Fatigue index (FI), Maximum Isometric Force (MIF), Time to MIF (Time) and rate of force development (RFD) were determined by a force sensor. Muscle thickness was obtained using ultrasound images. All measures were taken pre- and post-training. Additionally, electromyographic signal (EMG) was evaluated in the last set of each exercise condition. Post-exercise fatigue was higher with full ROM as well as loss of MIF. Full ROM also induced greater. EMG showed greater activation of the Clavicular portion and Sternal portion of pectoralis major muscle and lower in the anterior portion of deltoid muscle when full ROM was performed. Muscle thickness of the pectoralis major muscle increased post-exercise. We concluded that training with partial ROM enables higher workloads with lower loss of muscle function.

Evaluation of Training with Elastic Bands on Strength and Fatigue Indicators in Paralympic Powerlifting.

BACKGROUND: Variable resistance training has recently become a component of strength and conditioning programs. OBJECTIVE: This randomized counterbalanced cross-over study aimed to investigate the use of elastic bands (EB) and the traditional method (TRAD) and force indicators in a training session. METHODS: 12 Paralympic athletes (age: 28.60 ± 7.60 years) participated in this three-week study. In the first week, the participants were familiarized with EB and TRAD and were tested for maximal repetition (1-RM). The research occurred in weeks 2 and 3, which included the pre-post training, during which the following measures were extracted: maximum isometric force (MIF), the peak torque (PT), rate of force development (RFD), fatigue index (FI), and time to MIF (Time). The athletes performed two tests, EB and TRAD, separated by a one-week interval. RESULTS: Significant differences were found between the pre- and post-test for 1RM (p = 0.018, η2p = 0.412), MIF (p = 0.011, η2p = 0.415), PT (p = 0.012, η2p = 0.413), and RFD (p = 0.0002, η2p = 0.761). With the use of EB, there was a difference in RFD between TRAD before and EB after (p = 0.016, η2p = 0.761). There were significant differences in the before and after for FI between TRAD and EB (p < 0.001) and for Time (p < 0.001), indicating that training with the use of elastic bands promotes overload, characterized by increased fatigue and decreased strength. CONCLUSIONS: Training with EB did not decrease 1RM, PT, MIF or RFD, however, there was an increase in fatigue and time to reach MIF when compared to the method with fixed resistance.

Split or full-body workout routine: which is best to increase muscle strength and hypertrophy?

OBJECTIVE: To compare the effects of different resistance training programs on measures of muscle strength and hypertrophy. METHODS: Sixty-seven untrained subjects were randomized to one of two groups: Split Workout Routine (n=35), in which muscle groups were trained twice per week in an A/B split consisting of eight sets per session, or Full-Body Workout Routine (n=32), in which muscle groups were trained four times per week with four and eight sets per session. Both groups performed eight to 12 repetition maximum per set, with 60 seconds of rest between sets. Maximal strength and muscle thickness were assessed at baseline and after eight weeks of training. RESULTS: A significant main effect of time (pre versus post) was observed for maximal strength in the bench press and squat exercises and thickness of the elbow extensor, elbow flexor and quadriceps femoris muscles. Selected variables did not differ significantly between groups. CONCLUSION: Resistance training twice or four times per week has similar effects on neuromuscular adaptation, provided weekly set volume is equal.

Are Strength Indicators and Skin Temperature Affected by the Type of Warm-Up in Paralympic Powerlifting Athletes?

(1) Background: the present study aimed to evaluate the effect of different types of warm-ups on the strength and skin temperature of Paralympic powerlifting athletes. (2) Methods: the participants were 15 male Paralympic powerlifting athletes. The effects of three different types of warm-up (without warm-up (WW), traditional warm-up (TW), or stretching warm-up (SW)) were analyzed on static and dynamic strength tests as well as in the skin temperature, which was monitored by thermal imaging. (3) Results: no differences in the dynamic and static indicators of the force were shown in relation to the different types of warm-ups. No significant differences were found in relation to peak torque (p = 0.055, F = 4.560, η2p = 0.246 medium effect), and one-repetition maximum (p = 0.139, F = 3.191, η2p = 0.186, medium effect) between the different types of warm-ups. In the thermographic analysis, there was a significant difference only in the pectoral muscle clavicular portion between the TW (33.04 ± 0.71 °C) and the WW (32.51 ± 0.74 °C) (p = 0.038). The TW method also presented slightly higher values than the SW and WW in the pectoral muscles sternal portion and the deltoid anterior portion, but with p-value > 0.05. (4) Conclusions: the types of warm-ups studied do not seem to interfere with the performance of Paralympic Powerlifting athletes. However, the thermal images showed that traditional warm-up best meets the objectives expected for this preparation phase.

Static and Dynamic Strength Indicators in Paralympic Power-Lifters with and without Spinal Cord Injury.

BACKGROUND: In Paralympic powerlifting (PP), athletes with and without spinal cord injury (SCI) compete in the same category. Athletes with SCI may be at a disadvantage in relation to the production of muscle strength and the execution of motor techniques. OBJECTIVE: To analyze the indicators force, dynamic and static, at different intensities, on performance in athletes with and without SCI. METHODS: The sample was composed of two groups of PP athletes: SCI (30.57 ± 4.20 years) and other deficiencies (OD; 25.67 ± 4.52 years). Athletes performed a test of maximum isometric force (MIF), time to MIF (Time), rate of force development (RFD), impulse, variability and fatigue index (FI), dynamic tests Mean Propulsive Velocity (MPV), Maximum Velocity (Vmax) and Power. RESULTS: There were differences in the SCI in relation to OD, 50% 1RM (p < 0.05), in relation to MPV and Vmax. There were no differences in the static force indicators. Regarding EMG, there were differences between the SCI triceps in relation to the previous deltoid (p = 0.012). CONCLUSION: We concluded that the static and dynamic strength indicators are similar in Paralympic powerlifting athletes with spinal cord injury and other disabilities.

Physiological and Biochemical Evaluation of Different Types of Recovery in National Level Paralympic Powerlifting.

BACKGROUND: Recovery from training is vital as it ensures training and performance to continue at high intensities and longer durations to stimulate the body and cause further adaptations. OBJECTIVE: To evaluate different methods of post-workout recovery in Paralympic powerlifting athletes. METHODS: Twelve male athletes participated (25.4 ± 3.3 years; 70.3 ± 12.1 kg). The presence of muscle edema, pain threshold, plasma cytokines, and performance measurement were evaluated five times. The recovery methods used in this study were passive recovery (PR), dry needling (DN), and cold-water immersion (CWI). RESULTS: The data analysis showed that the maximal force decreased compared to the pretest value at 15 min and 2 h. The results also revealed that CWI and DN increased Interleukin 2 (IL-2) levels from 24 to 48 h more than that from 2 h to 24 h. After DN, muscle thickness did not increase significantly in any of the muscles, and after 2 h, muscle thickness decreased significantly again in the major pectoralis muscle. After CWI, pain pressure stabilized after 15 min and increased significantly again after 2 h for acromial pectoralis. CONCLUSION: The strength training sessions generate several changes in metabolism and different recovery methods contribute differently to maintain homeostasis in Paralympic powerlifting athletes.

Evaluation of Strength and Muscle Activation Indicators in Sticking Point Region of National-Level Paralympic Powerlifting Athletes.

BACKGROUND: The sticking region is considered an intervening factor in the performance of the bench press with high loads. OBJECTIVE: To evaluate the strength indicators in the sticking point region in Powerlifting Paralympic athletes. METHODS: Twelve Brazilian Powerlifting Paralympic athletes performed maximum isometric force (MIF), rate of force development (RFD), time at MIF, velocity, dynamic time in sticking, and surface electromyography in several distances from the bar to the chest. RESULTS: For velocity, there was a difference between the pre-sticking and sticking region (1.98 ± 0.32 and 1.30 ± 0.43, p = 0.039) and dynamic time between the pre-sticking and the sticking region (0.40 ± 0.16 and 0.97 ± 0.37, p = 00.021). In static test for the MIF, differences were found between 5.0 cm and 15.0 cm (CI 95% 784; 1088; p = 0.010) and between 10.0 cm and 5.0 cm (CI 95% 527; 768; p < 0.001). Regarding the RFD, differences were found (CI 95% 938; 1240; p = 0.004) between 5.0 cm and 25.0 cm and between 10.0 cm and 25.0 cm (CI 95% 513; 732; p < 0.001). In relation to time, there were differences between 5.0 cm and 15.0 cm (CI 95% 0.330; 0.515; p < 0.001), 5.0 cm, and 25.0 cm (CI 95% 0.928; 1.345; p = 0.001), 10.0 cm and 15.0 cm (p < 0.05) and 15.0 cm and 25.0 cm (p < 0.05). No significant differences were observed between the muscles in electromyography, although the triceps showed the highest muscle activation values. CONCLUSIONS: The maximum isometric force, rate of force development, time, velocity, and dynamic time had lower values, especially in the initial and intermediate phases in the sticking region.

Comparison of the Local Temperature, Lactate and Glucose After Three Different Strength Training Methods.

This study aimed to evaluate the local temperature, lactate, and blood glucose in three strength training methods. The study included 12 male subjects; (22.15 ± 5.77 years, 76.85 ± 9.15 kg, 1.72 ± 0.09 m), with minimum of 12 months of strength training experience, and all participated in the three training methods: the occlusion training (Kaatsu); the tension training (Tension); and the traditional training (Traditional). The Kaatsu training consisted in 3 sets of 10RM with occlusion device in both arms inflated to a 130% occlusion pressure. In addition, the tension method was performed with 30% of 1RM and the traditional training, consisted in 10 repetitions with 80% RM. Regarding the temperature variation, differences were observed between the Kaatsu and Traditional methods in relation to Tension (p = .049, η 2 p = 0.187). While for blood glucose (p = .351, η 2 p = 0.075) and lactate (p = .722, η 2 p = 0.022) there were no differences between the methods. Regarding the temperature (°C) measured by thermography and asymmetry, the right side showed a decrease in the post-test, in relation to the pre-test, in all methods (p < .05, η 2 p > 0.150). The left (p = .035, η 2 p = 0.301) and right (p = .012, η 2 p = 0.324) sides showed a decrease in temperature, in the post-test in relation to the pre-test, in the Kaatsu and traditional method. In asymmetry, the three methods showed an increase in the post-test in relation to the pre-test (p = .042, η 2 p = 0.158). In conclusion, tension method seems to stimulate greater heat production than the other methods. This information can help coaches to choose among these training methods according to the desired physiological response.

Ischemic Preconditioning Improves Resistance Training Session Performance.

ABSTRACT: da Silva Novaes, J, da Silva Telles, LG, Monteiro, ER, da Silva Araujo, G, Vingren, JL, Silva Panza, P, Reis, VM, Laterza, MC, and Vianna, JM. Ischemic preconditioning improves resistance training session performance. J Strength Cond Res 35(11): 2993-2998, 2021-The aim of this study was to investigate the acute effect of ischemic preconditioning (IPC) in a resistance exercise (RE) training session on the number of repetitions performed, total volume, and rating of perceived exertion in recreationally trained and normotensive men. Sixteen recreationally trained and normotensive men completed 3 RE sessions in a counterbalanced and randomized order: (a) IPC protocol using 220 mm Hg followed by RE (IPC), (b) IPC cuff control protocol with 20 mm Hg followed by RE (CUFF), and (c) no IPC (control) followed by RE (CON). RE was performed with 3 sets of each exercise (bench press, leg press, lateral pulldown, hack machine squat, shoulder press, and Smith back squat) until concentric muscular failure, at 80% of one repetition maximum, with 90 seconds of rest between sets and 2 minutes of rest between exercises. Ischemic preconditioning and CUFF consisted of 4 cycles of 5 minutes of occlusion/low pressure alternating with 5 minutes of no occlusion (0 mm Hg) using a pneumatic tourniquet applied around the subaxillary region of the upper arm. For each condition, the number of repetitions completed, total volume of work performed, and rating of perceived exertion were determined. No significant difference was found for rating of perceived exertion between any experimental protocol. Ischemic preconditioning significantly (p < 0.05) increased the number of repetitions across exercises. Consequently, total volume performed (sum of total number of repetitions x load for each exercise) was significantly higher in IPC (46,170 kg) compared with CON (34,069 kg) and CUFF (36,590 kg) across all exercises. This work may have important implications for athletic populations because it demonstrates increase in muscle performance outcomes during a single RE session. Therefore, performing IPC before RE could be an important exercise prescription recommendation to increase maximum repetition performance and total volume of work performed and thus potentially increase desired training adaptations (i.e., strength and hypertrophy).

The Influence of Warm-Up on Body Temperature and Strength Performance in Brazilian National-Level Paralympic Powerlifting Athletes.

Background and Objectives: The effects of warm-up in athletic success have gained strong attention in recent studies. There is, however, a wide gap in awareness of the warm-up process to be followed, especially in Paralympic powerlifting (PP) athletes. This study aimed to analyze different types of warm-up on the physical performance of PP athletes. Materials and Methods: The sample consisted of 12 elite Brazilian PP male athletes (age, 24.14 ± 6.21 years; bodyweight, 81.67 ± 17.36 kg). The athletes performed maximum isometric force (MIF), rate of force development (RFD), and speed test (Vmax) in three different methods of warm-up. Tympanic temperature was used to estimate the central body temperature. Results: A significant difference was observed for MIF in the without warm-up (WW) condition in relation to the traditional warm-up (TW) and stretching warm-up (SW) (p = 0.005, η2p = 0.454, high effect). On the contrary, no significant differences were observed in RFD, fatigue index (FI) and time in the different types of warm up (p > 0.05). Furthermore, no significant differences were observed in relation to the maximum repetition (p = 0.121, η2p = 0.275, medium effect) or the maximum speed (p = 0.712, η2p = 0.033, low effect) between the different types of warm up. In relation to temperature, significant differences were found for the TW in relation to the "before" and "after" conditions. In addition, differences were found between WW in the "after" condition and SW. In addition, WW demonstrated a significant difference in relation to TW in the "10 min later" condition (F = 26.87, p = 0.05, η2p = 0.710, high effect). Conclusions: The different types of warm-up methods did not seem to provide significant differences in the force indicators in elite PP athletes.

Evaluation of Muscle Damage, Body Temperature, Peak Torque, and Fatigue Index in Three Different Methods of Strength Gain.

The aim of this study was to evaluate and compare three different strength training protocols for the lower limbs by using biochemical indicators of muscle damage, thermographic analysis, and neuromuscular performance. In total, 10 men (age: 22.50 ± 2.84 years; weight, 75.45 ± 6.86 kg) completed the study. All the athletes were subjected to three methods of resistance training (RT): traditional, tension, and occlusion training. Serum concentrations of creatine kinase, lactate dehydrogenase, aspartate aminotransferase, and alanine aminotransferase were used as indicators of muscle damage. To measure muscle strength, the peak force, and fatigue index were determined using a Kratos load cell. Images were captured using an infrared camera (FLIR T640sc). The vascular occlusion method demonstrated a 33% reduction in posttraining peak torque (p < 0.001; η2p: 2.74), which was recovered within 24 h (p < 0.001; η2p: 1.08). The thermographic analysis revealed a reduction in skin temperature in both thighs after the tension (-9.37%) and vascular occlusion (-6.01%) methods. In conclusion, the occlusion training seems to provide additional benefits as compared to the other two methods of strength training.