High-intensity Training Research Articles

Can Eccentric-only Resistance Training Decrease Passive Muscle Stiffness while Increasing Size and Strength of Hamstrings?

Resistance training may be empirically believed to increase passive muscle stiffness. Meanwhile, a recent study showed that the passive stiffness of a specific hamstring muscle acutely decreased after eccentric-only resistance exercise at long muscle lengths with a long contraction duration (LL). To extend this finding, the present study investigated the chronic effects of eccentric-only resistance training with LL at different weekly frequencies on the passive stiffness of the biarticular hamstring muscles. Thirty-six healthy young males were assigned into two training groups with two and three weekly sessions (W2 and W3, n = 12, respectively) and a control group (CON, n = 12). The participants in both training groups performed eccentric-only stiff-leg deadlift at 50-100% of exercise range of motion (0% = upright position) with 5 s per repetition for 10 weeks. Before and after the intervention period, the shear moduli of the biarticular hamstring muscles, maximal voluntary isometric torque of knee flexion, and volumes of the individual hamstring muscles were measured. In W3, the shear modulus of the semimembranosus (-11.4%) significantly decreased, whereas those of the other biarticular muscles did not change. There were no significant changes in the shear moduli of the biarticular hamstring muscles in W2 or CON. The isometric torque (20.3 and 26.2%, respectively) and semimembranosus volume (5.7% and 7.4%, respectively) were significantly increased in W2 and W3. Passive stiffness of a specific muscle could be chronically decreased when eccentric-only resistance training with LL is performed at a relatively high weekly frequency with a high total training volume. Our training modality may be a promising strategy for decreasing passive muscle stiffness while increasing muscular strength and size.

Airborne acoustic assessment of impact-resistant fitness flooring systems

Fitness facilities in residential and mixed-used commercial buildings introduce important acoustic design challenges that must be considered in a building. Cardio activities such as running on treadmills, group classes for high intensity training, and weight training areas introduce high levels of unwanted noise and vibration into a building structure. Isolated floor constructions are generally coordinated and implemented during design but are not practical when buildings are completed and occupied. Impact-resistant fitness flooring systems are typically explored and installed as an alternate approach to reduce the transmission of impact noise and vibration. Non-standardized field airborne noise measurements of weight drops were conducted on an existing gym and on four possible impact-resistant fitness flooring upgrades to assess the reduction of impact noise levels in the offices located below the gym. The measurements were also compared to the HVAC background noise levels to observe the increase above background conditions and provide a subjective evaluation. The results of the measurements show that impact-resistant fitness flooring systems provide a noticeable reduction of impact noise, compared to standard fitness flooring systems. The results also show that impact-resistant fitness flooring systems that include specialty engineered shock pads as a base layer provide a significant reduction of impact noise levels.

Meldonium Supplementation in Professional Athletes: Career Destroyer or Lifesaver?

Meldonium is a substance with known anti-anginal effects demonstrated by numerous studies and human clinical trials; however, it does not possess marketing authorization within the European Union, only in ex-Soviet republics. Since 2016, meldonium has been included by the World Anti-doping Agency (WADA) on the S4 list of metabolic modulators. In performance athletes, meldonium is now considered a doping agent due to its capacity to decrease lactate production during and after exercise, its capability to enhance the storage and utilization of glycogen, and its protective action against oxidative stress. Together, these attributes can significantly improve aerobic endurance, cardiac function, and capacityas well as shorten recovery times (allowing higher intensity training), thereby enhancing performance. The purpose of this review is to highlight the most important mechanisms underlying the protective effect of meldonium against mitochondrial dysfunction (MD), which is responsible for oxidative stress, inflammation, and the cardiac changes known as "athletic heart syndrome."Meldonium acts as an inhibitor of γ-butyrobetaine hydroxylase (BBOX), preventing the de novo synthesis of carnitine and its absorption at the intestinal level via the organic cation/carnitine transporter 2 (OCTN2) and directing the oxidation of fatty acids to the peroxisomes. The decrease in mitochondrial β-oxidation of fatty acids leads to a reduction in lipid peroxidation products that cause oxidative stress and prevent the formation of acyl/acetyl-carnitines involved in numerous pathological disorders. Given the recent findings of the potentially detrimental effects of prolonged high-intensity exercise on cardiovascular health and coronary atherosclerosis, there may be legitimate arguments for the justification of the use of substances likemeldonium as protective supplements for athletes.

Right ventricular remodeling induced by prolonged excessive endurance exercise is mediated by upregulating Wnt/β-catenin signaling in rats

BackgroundThe aim of this study was to develop an animal model to investigate whether prolonged intensive endurance exercise induces RV remodeling, taking into account the involvement of Wnt/β-catenin signaling. MethodsFour-week-old male Wistar rats (100 to 125 g) were assigned to four groups (n = 8/group): 1) sixteen weeks of intensive (36 m/min) exercise (INT), 2) twelve weeks of the intensive exercise followed by four weeks of moderate intensity (18 m/min) exercise (INT + MOD), 3) twelve weeks of the intensive exercise followed by four weeks of detraining (INT + DT), and 4) sedentary rats (SED). The exercise protocols were performed five days a week for one h/day. Echocardiography, real-time PCR, western blotting, and histological staining were performed at the end of week sixteen. ResultsINT rats developed concentric hypertrophy without diastolic dysfunction compared to SED (p = 0.006) and INT + DT (p = 0.035). Wnt1, β-catenin and CyclinD1 proteins in the training groups were significantly higher than SED rats (p < 0.001). Interestingly, INT rats had higher protein levels than INT + DT and INT + MOD (p < 0.001), with higher gene expression compared to SED rats (p < 0.05). There was also a significant increase in collagen deposition in INT rats compared to SED (p = 0.046) and INT + DT (p = 0.034). Furthermore, INT + MOD and INT + DT rats did not show any adverse structural, functional, or histological changes. ConclusionsLong-term intensive endurance training seems to be associated with increased collagen deposition and wall thickness in the RV through Wnt/β-catenin signaling (which is concentration dependent), without changes in diastolic function. Clinical perspectiveOver the past decades, there has been an ongoing debate about whether the structural and functional adaptations of the cardiovascular system in trained endurance athletes are benign physiological responses to training or potentially pathological changes related to disease. While the adaptations of the left heart are well-documented, the remodeling of the right heart remains a subject of discussion. To gain insights into the ability of sustained high-intensity exercise to cause adverse right ventricular (RV) remodeling, we conducted an experimental study in which male rats were trained to run vigorously for 1 h daily over a 16-week period and compared them to a parallel group of sedentary control rats. Our findings revealed that intense long-term exercise induced morphological changes along with fibrosis affecting the RV. These fibrotic changes were a result of the 16-week vigorous exercise training regimen. If these results are confirmed in humans, they suggest that prolonged high-intensity endurance exercise training may lead to adverse cardiac remodeling. Our findings have important potential implications for the assessment of cardiac remodeling in individuals engaged in high-level exercise training.

Endurance Training Improves Leg Proton Release and Decreases Potassium Release During High-Intensity Exercise in Normoxia and Hypobaric Hypoxia.

To assess the impact of endurance training on skeletal muscle release of H+ and K+. Nine participants performed one-legged knee extension endurance training at moderate and high intensities (70%-85% of Wpeak), three to four sessions·week-1 for 6 weeks. Post-training, the trained and untrained (control) leg performed two-legged knee extension at low, moderate, and high intensities (40%, 62%, and 83% of Wpeak) in normoxia and hypoxia (~4000 m). The legs were exercised simultaneously to ensure identical arterial inflow concentrations of ions and metabolites, and identical power output was controlled by visual feedback. Leg blood flow was measured (ultrasound Doppler), and acid-base variables, lactate- and K+ concentrations were assessed in arterial and femoral venous blood to study K+ and H+ release. Ion transporter abundances were assessed in muscle biopsies. Lactate-dependent H+ release was similar in hypoxia to normoxia (p = 0.168) and was lower in the trained than the control leg at low-moderate intensities (p = 0.060-0.006) but similar during high-intensity exercise. Lactate-independent and total H+ releases were higher in hypoxia (p < 0.05) and increased more with power output in the trained leg (leg-by-power output interactions: p = 0.02). K+ release was similar at low intensity but lower in the trained leg during high-intensity exercise in normoxia (p = 0.024) and hypoxia (p = 0.007). The trained leg had higher abundances of Na+/H+ exchanger 1 (p = 0.047) and Na+/K+ pump subunit α (p = 0.036). Moderate- to high-intensity endurance training increases lactate-independent H+ release and reduces K+ release during high-intensity exercise, coinciding with increased Na+/H+ exchanger 1 and Na+/K+ pump subunit α muscle abundances.

Balancing physical development and health in adolescents through controlled High-Intensity Training

Background and Study Aim. Considering the growing interest in high-intensity training (HIT) among the youth, it is crucial to explore its impact not only on improving physical fitness but also on the overall health of adolescents. The aim of this study was to assess how HIT can contribute to the development of physical qualities in adolescents while minimizing the risks of excessive strain. Materials and Methods. The study encompassed 28 students (14±0.9 years) from a lyceum in Kharkiv, Ukraine. The participants were divided into a control group (CG, n=14; including boys - n=7 and girls n=7) and an experimental group (EG, n=14; including boys - n=7 and girls n=7). The EG participated in high-intensity training sessions twice a week, with each session lasting 20 minutes. The program's effectiveness was evaluated using a series of physical ability tests. PyCharm Community Edition integrated development environment was used for the analysis and visualization of the obtained data. The software code was written in Python. The experiment was conducted in Kharkiv (Ukraine), located in a war zone since February 2022. The requirements of the military administration for ensuring the safety of experiment participants were observed. Results. After the training program, boys from the EG showed improvement in tests on speed, coordination, and motor skills (p&lt;0.05). Girls in the EG demonstrated significant improvement in the "Sit-up from a sitting position in 30 seconds" test (p&lt;0.05), as well as improvements in speed and coordination tests. Conclusions. High-intensity workouts can be effectively integrated into the physical education program for teenagers, provided that caution is exercised and the workload is monitored. The results confirm that such an approach contributes to the development of physical qualities and supports the health of teenagers. This suggests a nuanced understanding of how such programs can be optimized for different genders to enhance physical education outcomes.

Effects of Center Based vs. Telerehabilitation using an Interval and Continuous Aerobic Training among Post-Coronary Revascularization Patients-A Randomized Controlled Trial

Background: This investigation used continuous aerobic and high-intensity interval training to compare the differences between centre-based and telerehabilitation. This study seeks to identify the most efficient rehabilitation strategy positioned to empower patients on their path to recovery and well-being in the contemporary era of cardiac care. Methodology: The study was a single-blinded, randomized controlled trial involving 80 patients who had undergone coronary revascularization procedures, were enrolled in the cardiac rehabilitation department, and were eligible for Phase-III CR. Patients were divided into Group A, receiving centre-based Continuous Moderate-Intensity Aerobic Exercise, 3–4 days a week, at 50%-70% of MHR. Group B received high-intensity interval-based training for 3–4 days and at four subsequent intervals. Telerehabilitation was conducted with Group C following the same protocol as Group A and Group D following the same protocol as Group B, while each group had n=20 participants. Results: The within-group analysis showed significant improvements in the 6-Minute Walk Test (6MWT) and Self-reported Seven-Day Physical Activity Questionnaire (PAR) across all groups (p&lt;0.001). Significant improvements in the Rate of Perceived Exertion (RPE) were found in Groups A and B (p&lt;0.05). ANOVA results indicated that centre-based rehabilitation was significantly more effective than telerehabilitation in improving 6MWT and RPE scores (p&lt;0.05). Conclusion: Centre-based intervention is more effective than telerehabilitation in Phase-III Cardia Rehabilitation patients. However, high-intensity interval-based training was more effective in centre-based, while continuous moderate-intensity aerobic exercise was effective in telerehabilitation. Keywords: Aerobic Exercises, Cardiac Rehabilitation, Coronary Artery, Physical Activity.

Anabolic/Catabolic Hormone Imbalance but Still Jumping Further? Negative Association of Free Testosterone With Jumping Performance in Elite Handball Players Following a Preparatory Period

ABSTRACT Purpose: The present study investigated the effects of a 10-week preparatory training period on biomarkers and jumping performance and associations of changes in biomarkers, load, and jumping performance from the beginning (PRE) to the end of the preparatory period (POST) in elite handball players. Methods: Seventeen elite handball players competing in the first Slovenian men’s League were recruited. Training, competition and academic loads were reported weekly, while biomarkers and jumping performance were assessed at PRE and POST. Results: At POST, decreased levels of free testosterone (large effect size [ES] = -1.69, p < .001) and free testosterone to cortisol ratio [FTCR] (large ES = −.95, p = .004) were observed; whereas, better performance on the single leg lateral hop test [SLLH] (large ES = .85, p = .007) and single leg triple hop test [SLTH] (large ES = 1.05, p = .002) were observed compared to PRE. Furthermore, changes in FTCR correlated with changes in cortisol (high r = -.751, p = .001), SLLH (moderate r = -.603, p = .022), and SLTH (moderate r = -.643, p = .013), while changes in free testosterone correlated with SLTH (moderate r = -.645, p = .013). Conclusions: High intensity trainings with a saturated competition schedule can result in disturbed anabolic/catabolic hormone ratio observed through FTCR decrease, which could indicate either an optimal state or early exhaustiveness. It seems that SLLH and SLTH are more sensitive to changes in biomarkers than a single leg hop test. Sport professionals may use the results for individualized monitoring of an athlete’s health and performance, specifically, as an aid for adjusting training loads accordingly to prevent performance declines and potential injury/illness events.

Enhancing physical fitness through Crossfit for 15-16-year-old high school students

Background and Study Aim. CrossFit represents a high-intensity functional training that has recently gained popularity among the youth. At the same time, restrictions imposed by military actions require different approaches to organizing CrossFit sessions. The most acceptable solution in such a situation is online education and training. The purpose of this study was to investigate the impact of CrossFit sessions within the framework of remote physical education on the physical fitness indicators of high school students. Materials and Methods. The study involved 27 students (aged 15-16 years) from a 10th-grade class at a school located in a war conflict zone (Kharkiv, Ukraine). The group consisted of 11 boys and 16 girls. Due to the military conflict and corresponding restrictions, physical education was conducted remotely. Physical education classes were held three times a week, lasting 45 minutes each. The structure of the lesson included 30 minutes of synchronous online work with the teacher and 15 minutes for independent task completion. Tests aimed at measuring strength, endurance, flexibility, and speed were used to assess the impact of CrossFit programs on physical fitness. Data were collected at the beginning and end of the experiment. The experiment was conducted over 8 weeks. Testing was carried out at home by students under the control and guidance of the teacher via video link during the first three lessons. Results. The test results confirm improvement in all indicators. The boys increased their plank hold duration from 48 seconds to 53 seconds, and the girls from 46 seconds to 52 seconds. In the squat series, an increase in indicators was noted: for boys from 21 to 25 in the third series. Girls also showed significant improvement across all squat series. The boys' speed-strength indicators improved from 43 cm to 46 cm. Girls demonstrated improvement in performing "Burpees" within 60 seconds, increasing the number of repetitions from 8 to 12. Conclusions. The study results indicate that CrossFit effectively enhances the physical fitness of high school students. However, the improvement in girls occurs to a slightly lesser extent compared to boys. This may be due to the initial level of physical fitness and individual physiological characteristics.

Analysis of the Effectiveness of High-Intensity Interval Training Methods in Improving Basketball Players Fitness

This research aims to analyze the effectiveness of High-Intensity Interval Training (HIIT) in improving the fitness of basketball players. Employing a literature review methodology, this study explores recent findings related to the application of HIIT in the context of basketball sports. The literature analysis involves searching and screening various scientific articles covering aspects such as improved cardiorespiratory fitness, muscle strength, time efficiency, and safety considerations. The results indicate that HIIT holds significant potential in enhancing the cardiorespiratory fitness of basketball players, with positive effects on aerobic capacity and cardiorespiratory endurance. Furthermore, HIIT has also shown a positive impact on increasing muscle strength and endurance. The effectiveness of HIIT can be observed in its time efficiency, as this high-intensity training program can deliver significant results in a shorter time compared to conventional training methods. However, the study also highlights the importance of considering the risks and safety considerations in implementing HIIT, emphasizing the need for an individualized approach and careful monitoring. Thus, this research provides a solid foundation for the development of more focused and effective training programs to enhance the performance of basketball players. The practical implications of these findings can assist coaches and fitness professionals in designing exercise programs tailored to the specific needs of basketball players, taking into account cardiorespiratory aspects, muscle strength, time efficiency, and safety.

Facilitators and Barriers to Implementing High-Intensity Gait Training in Inpatient Stroke Rehabilitation: A Mixed-Methods Study.

(1) Background: High-intensity gait training (HIT) is a recommended intervention that improves walking function (e.g., speed and distance) in individuals who are undergoing stroke rehabilitation. This study explored clinicians' perceived barriers and facilitators to implementing HIT utilizing a mixed-methods approach comprising a survey and exploratory qualitative research. (2) Methods: Clinicians (n = 13) who were implementing HIT at three facilities participated. We collected and analyzed data using the consolidated framework for implementation research. Three focus groups were recorded and transcribed, and data were coded and thematically categorized. (3) Results: Survey results identified that the facilitators with a strong impact on implementation were access to knowledge/resources and intervention knowledge/beliefs. The only agreed-upon barrier with a strong impact was lack of tension for change. The focus groups resulted in 87 quotes that were coded into 27 constructs. Frequently cited outer setting facilitators were cosmopolitanism and peer pressure, and the only barrier was related to the patient needs. Innovation characteristics that were facilitators included relative advantage and design quality and packaging, and complexity was a barrier. Inner setting facilitators included networks and communication, learning climate, leadership engagement, and readiness for implementation. However, communication, leadership engagement, and available resources were also barriers. Regarding characteristics of individuals, knowledge and beliefs were both barriers and facilitators. In the implementation process domain, common facilitators were formally appointed implementation leaders and innovation participants. Barriers in this domain were related to the patients. (4) Conclusions: Clinicians identified many barriers and facilitators to implementing HIT that often varied between facilities. Further research is warranted to deepen our understanding of clinicians' experiences with HIT implementation.

Effects of Acute Piano Performance With Blood Flow Restriction on Upper Limb Muscle and Perceptual Response in Pianists.

Long-term and prolonged piano performance does not provide essential skeletal muscle training benefits while increasing the risk of injury to the upper extremities. Unlike high-intensity exercise training, moderate blood flow restriction (BFR) training has been found to improve neuromuscular mechanisms with a variety of physical exercises (machine, elastic band, walking, electrical stimulation, and body weight). We investigated the physiological and perceptual responses related to piano performance with or without BFRbased on acute responses of neuromuscular mechanisms.Student or professional pianists (n=7) performed the "Revolutionary Etude" on the piano with (Piano-BFR) and without (Piano-Ctrl) BFR. During the Piano-BFR performance, 150-180 mmHg of cuff pressure was applied around the most proximal region of both arms as a moderate BFR. Changes in upper limb girth, muscle thickness, and hand grip strength were measured before and immediately after the performance. After the performance, perceptual and other responses were recorded.Immediately after the performance, the Piano-BFR condition induced greater changes in girth (forearm and upper arm), muscle thickness (forearm), and handgrip strength than the Piano-Ctrl condition.Piano-BFRwas (p<0.01) higher than Piano-Ctrl on eight questions regarding perceptual response (upper arm fatigue and difficulty playing the piano). Piano performance with BFR was revealed to increase upper extremity muscle size and fatigue in pianists after playing. Piano performance with BFR was revealed to increase upper extremity muscle size and fatigue in pianists after playing. The effect of BFR on neuromuscular mechanisms on piano performance was greater in the forearm than in the upper arm.

Mood, Cognitive Function, and Plasma Kynurenine Metabolites Responses Following Severe Changes in Physical Activity.

To monitor changes in mood, cognitive function, brain electrical activity, and circulating kynurenine pathway metabolites in response to a 3-wk severe physical activity (PA) restriction, followed by 3 wk of resumed activity adding resistance and high-intensity interval exercise training. Twenty healthy participants (14 males, 6 females; 25.4 ± 5.2 yr) underwent 3 wk of limited PA using forearm crutches with one leg suspended (INACT) and then 3 wk of resumed activity plus supervised resistance and high-intensity interval training sessions (ACT, three to six sessions per week). At baseline, after INACT, and then after ACT, venous blood was sampled for analysis of major kynurenine pathway metabolites, a short version of the International Physical Activity Questionnaire, Hospital Anxiety and Depression Scale (HADS) and Profile of Mood States (POMS) questionnaires were completed, and cognitive tests with electroencephalography were performed. During INACT, the depression score on the HADS scale tended to increase (3.5 to 6.8; P = 0.065), whereas it was reduced with ACT compared with after INACT (2.8; P = 0.022). On the POMS scale, depression, fatigue, and confusion increased within INACT ( P < 0.05). Notably, subjects exhibited considerable variability, and those experiencing depression symptoms recorded by the HADS scale ( n = 4) displayed distinct mood disturbances on POMS. All HADS and POMS scores were fully restored to baseline with ACT. Neither INACT nor ACT induced significant changes in cognition, brain electrical activity, or kynurenine pathway metabolites ( P > 0.05). Although young healthy individuals with 3 wk of severely restricted PA do not undergo changes in circulating kynurenine pathway metabolites, cognitive performance, and brain electrical activity, their mood response is quite variable, and depression develops in some. Three weeks of resuming mobility plus exercise training reversed the mood profile.

Evaluating the impact of three dosages of royal jelly supplement on malondialdehyde levels and pain intensity following high-intensity weight training

Evaluating the impact of three dosages of royal jelly supplement on malondialdehyde levels and pain intensity following high-intensity weight training

Aspects of the dynamics of osteogenesis and bone tissue resorption markers concentrations in elite biathlonists due to the compression specificity of the cyclic training aids used at the stages of the early season

Aim: study the dynamics of osteogenesis and bone resorption markers in elite biathlonists owing to the “compression” specifics of cyclic training aids, mainly used at the stages of the early season of the annual training cycle.Materials and methods: 23 elite biathlonists undergoing centralized training as the members of the Russian national team took part in the study.Results: no changes in the P1NP amounts reaching a reliable level were recorded throughout the early season. The average group osteocalcin amount at the precompetition stage significantly (p &lt; 0,05) increased compared with that measured at the special preliminary stage. Dynamics of β-CrossLaps concentration showed significant (p &lt; 0,05) decrease during the transition from the general preliminary to the special preliminary stage.Conclusion: the degree of intense training activity influence on the activity of bone cells and in turn the response of bone tissue to training loads depend on a set of exercise parameters performed by the athlete, such as duration, intensity, specificity, recovery time and mechanical stress. Optimizing the ratio of cyclic aids with different levels of compression loads during specialized training promotes adaptive changes which protect bone tissue from resorption affected by intense physical exercises. When analyzing the levels of bone metabolism markers for diagnosis and monitoring disorders associated with skeletal overload which could occur high-intensity training loads, an individual approach as well as recognition of the load specifics and parameters performed by an athlete at a specific stage of the training macrocycle are required.

Acute Intermittent Hypoxia With High-Intensity Gait Training in Chronic Stroke: A Phase II Randomized Crossover Trial.

Studies in individuals with chronic stroke indicate high-intensity training (HIT) focused on walking improves locomotor function, which may be due to repeated activation of locomotor circuits and serotonin-dependent modulation of motor output. Separate studies in animals and individuals with spinal cord injury suggest acute intermittent hypoxia (AIH) can augment the effects of locomotor interventions through similar serotonin-dependent mechanisms, although no studies have coupled AIH with HIT in individuals poststroke. The goal of this study was to evaluate the safety and efficacy of AIH+HIT versus HIT alone in individuals with chronic stroke. This phase II double-blind randomized, crossover trial recruited individuals between 18 and 85 years old, >6 months poststroke, and self-selected speeds <1.0 m/s. Participants received up to 15 sessions of AIH for 30 minutes using 15 cycles of hypoxia (60-90 seconds; 8%-9% O2) and normoxia (30-60 seconds; 21% O2), followed by 1 hour of HIT targeting >75% heart rate reserve. The control condition received normoxia for 30 minutes before HIT. Following the first training phase, participants performed the second phase >1 month later. The primary outcomes were self-selected speed and fastest speed, a 6-minute walk test, and peak treadmill speed. A 3-way mixed-model ANOVA assessed the effects of time, training, and order of interventions. Of 55 individuals screened, 35 were randomized to AIH+HIT or normoxia+HIT first, and 28 individuals completed both interventions, revealing greater gains in self-selected speeds (0.14 [0.08-0.18] versus 0.05 [0.01-0.10] m/s), fastest speed (0.16 [0.10-0.21] versus 0.06 [0.02-0.10] m/s), and peak treadmill speed (0.21 [0.14-0.29] versus 0.11 [0.06-0.16] m/s) following AIH+HIT versus normoxia+HIT (P<0.01) with no order effects. Greater gains in spatiotemporal symmetry were observed with AIH+HIT, with worse outcomes for those prescribed serotonin-mediated antidepressant medications. AIH+HIT resulted in greater gains in locomotor function than normoxia+HIT. Subsequent phase III trials should further evaluate the efficacy of this intervention. URL: https://clinicaltrials.gov/; Unique identifier: NCT04472442.

Changes in Muscle Mass and Strength in Adolescents Following High-Intensity Functional Training with Bodyweight Resistance Exercises in Physical Education Lessons.

(1) Background: The growing prevalence of obesity, diabetes, hypertension, and declining physical fitness among children and adolescents due to sedentary lifestyles has increased attention toward preventive intervention to tackle this issue. This study investigated the age-related effects of high-intensity functional training (HIFT), based on bodyweight resistance exercises conducted during physical education lessons, on muscle mass and strength improvement. (2) Methods: Adolescent males (n = 116) were allocated to four HIFT experimental groups (EGs) and four standard physical education program control groups (CGs) according to age (15, 16, 17, and 18 years [y]). The changes in muscle mass (absolute and relative to height [SMI]), hand-grip strength (HGS), sit-ups (SUs), and standing broad jump (SBJ) were analyzed using two-way analysis of variance (ANOVA) with Bonferroni tests. (3) Results: HIFT significantly increased muscle mass and scores in all strength tests (p < 0.01), while chronological age was significant for HGS (p < 0.01). Interactions between HIFT and chronological age categories were observed for HGS (p = 0.01) and SBJ (p < 0.03). Detailed post hoc tests revealed improvement in muscle mass across all chronological age categories for both approaches (p < 0.05). The 18y-EG group improved HGS over their control peers (p < 0.01), the EG groups significantly improved their SU results (p < 0.01), and SBJ improved in the 15y-EG and 18y-EG groups compared to their control (p < 0.01). (4) Conclusions: This research highlights the effectiveness of a school-based HIFT program in promoting muscle mass gains and enhancing muscle strength among adolescents. The findings offer valuable insights for implementing bodyweight exercises during physical education classes.

Benefits of Training on the SHREDmill, a Non-motorized Resistance Treadmill

The SHREDmill, a non-motorized, non-curved resistance treadmill, offers significant benefits for sports training, particularly in activities requiring high speed and agility, such as football. Its design promotes natural running mechanics, crucial for performance enhancement and injury prevention. Customizable incline and resistance settings allow for tailored training to simulate specific athletic movements, enhancing both safety and effectiveness. Advanced software provides real-time feedback on performance metrics, enabling immediate adjustments and continuous improvement. The SHREDmill’s compact design supports high-intensity sprint training in confined spaces, making it ideal for gyms and training facilities. Athletes, such as football players benefit from the SHREDmill’s ability to replicate short sprints and explosive power, essential to their training regimen.

Long-Term High-Intensity Plyometric Training Increases Muscle Strength and Power of The Lower Body in Young Healthy Males

Long-Term High-Intensity Plyometric Training Increases Muscle Strength and Power of The Lower Body in Young Healthy Males

Handcycling with concurrent lower body low-frequency electromyostimulation significantly increases acute oxygen uptake in elite wheelchair basketball players: an acute crossover trial.

Wheelchair basketball (WCB) demands high-intensity training due to its intermittent nature. However, acute oxygen uptake (V˙O2) in handcycling is restricted. Combining handcycling with low-frequency electromyostimulation (LF-EMS) may enhance V˙O2 in elite WBC athletes. Randomized crossover trail. Twelve German national team WCB players (age: 25.6 [5.6] years, height: 1.75 [0.16] m, mass: 74.0 [21.7] kg, classification: 2.92 [1.26]). Participants underwent 2×5 min of handcycling (60 rpm, ¾ bodyweight resistance in watts) (HANDCYCLE) and 2×5 min of handcycling with concurrent LF-EMS (EMS_HANDCYCLE). LF-EMS (4Hz, 350µs, continuous stimulation) targeted gluteal, quadriceps, and calf muscles, adjusted to individual pain thresholds (buttocks: 69.5 [22.3] mA, thighs: 66.8 [20.0] mA, calves: 68.9 [31.5] mA). Significant mode-dependent differences between HANDCYCLE and EMS_HANDCYCLE were found in V˙O2 (17.60 [3.57] vs 19.23 [4.37] ml min-1 kg-1, p = 0.001) and oxygen pulse (16.69 [4.51] vs 18.41 [5.17] ml, p = 0.002). ΔLactate was significantly lower in HANDCYCLE (0.04 [0.28] vs 0.31 [0.26] mmol l-1). Although perceived effort did not differ (p = 0.293), discomfort was rated lower in HANDCYCLE (1.44 [1.28] vs 3.94 [2.14], p = 0.002). LF-EMS applied to the lower extremities increases oxygen demand during submaximal handcycling. Thus, longitudinal application of LF-EMS should be investigated as a potential training stimulus to improve aerobic capacity in wheelchair athletes.