Amateur boxing: physical and physiological attributes

Physical Capacities and Combat Performance Characteristics of Male and Female Olympic Boxers

Purpose: The study characterized the anthropometrical and cardiorespiratory profile, and the cardiorespiratory, bio-chemical and immunological responses to 3 × 3 min round (R) free-contact/combat boxing simulation, in elite Olympic Boxers (4 female and 10 male). Methods: The evaluation consisted of resting metabolic rate, anthropometric measurement, maximal graded test exercise (visit 1), free combat simulation (3 × 3 min R, 1 minute rest), and blood samples collected before, during and after the combat (visit 2). Results: Respectively, females and males had (mean±SD; or median: for non-parametric data) body fat percentage (17.2[3.5] and 4.6[0.8]%), predominantly mesomorphic somatotyping, and V ˙ O 2 MAX (50.0 ± 2.5 and 56.2 ± 5.2 ml.kg-1.min-1). The free combat simulation resulted in high cardiovascular strain [mean heart rate corresponding to R1: 92 ± 3; R2: 94 ± 2; and R3: 95 ± 2% of maximal HR] and blood chemistry indicative of acidosis (following R3: 7.21 ± 0.08 pH, bicarbonate 13.1 ± 3.6 mmol.L-1, carbon dioxide 13.9 ± 3.8 mmol.L-1, lactate 15.1 ± 3.8 mmol.L-1, and glucose 8.4 ± 1.3 mmol.L-1). Further, notable general catabolism, hematological and immune responses were evident post combat simulation (1-hour post R3: creatinine 95.2 ± 14.5 µmol.L-1, urea 6.4 ± 1.3 mmol.L-1, white blood cell accumulation 7.8 ± 2.6 × 109.L-1, hemoglobin 14.9 ± 0.8 g.dL-1 and hematocrit 43.7 ± 1.9%). Conclusions: Notable cardiovascular strain and acidosis are seen from the 3 × 3 free combat simulation whilst pronounced catabolism and immune responses are evident 1-hour post R3. This characterization is the first in male and female (who recently adopted the 3 × 3 min R format, as used by males) elite Olympic boxers and provides a characterization framework to assist practitioners and athletes in their attempts to deliver evidence-informed practice for specific conditioning session design.

Effects of short-term pre-competition weight loss on certain physiological parameters and strength change in elite boxers

BACKGROUND

Athletes in certain sports aim to gain an advantage by competing in a lower body mass class instead of competing in their own body mass class. This study aims to reveal certain physiologic and strength changes in elite male boxers who lost body mass rapidly before the competition.

METHODS

30 thirty boxers who were aged between 19-24 years and having a mean age of 7.4 years participated in the study. To evaluate the effect of short-term dietary intake interventions on body composition and muscle strength before the competition, boxers were divided into three groups: control (C), exercise+diet1 (E+D1) and exercise+diet2 (E+D2) groups. The dietary habits of the participants were controlled and they participated in the training program. The data of the study consisted of variables such as body mass, height, regional muscle mass, body fat percentage, biceps and femur bicondylar circumference measurements before the competitions. Isometric strength measurements of knee extensors and flexors and shoulder internal and external rotators were also recorded.

RESULTS

Physiologic parameters such as body mass change, BMI level, body fat percentage and leg muscle ratios of E+D2 were significantly decreased compared to C and E+D1 groups. Furthermore, submaximal and maximal strength production in knee extensors and flexors as well as shoulder internal and external rotators were significantly decreased in E+D2 compared to C and E+D1 groups.

CONCLUSION

The tendency to lose body mass quickly in a short of time may give the desired results in terms of BMI, body mass and fat percentage, but it may cause strength losses in boxers during the competition period.

Evaluation of the Effectiveness of In-Hospital Exercise Rehabilitation in Middle-Aged and Elderly Patients with Type 2 Diabetes Mellitus Combined with Sarcopenia Effect of Lifestyle Management on Disease Status in Patients with Type 2 Diabetes Mellitus

OBJECTIVE

The aim of this study was to explore the effects of in-hospital exercise rehabilitation on glucose and lipid metabolism and healthy physical fitness in middle-aged and elderly patients with type 2 diabetes mellitus (T2DM) combined with sarcopenia, and to provide a reference for the effective implementation of exercise rehabilitation for middle-aged and elderly patients with T2DM combined with sarcopenia in healthcare institutions.

METHODS

This study retrospectively included 122 patients with T2DM combined with sarcopenia treated at the General Hospital of Ningxia Medical University from August 2017 to August 2020 and randomly divided into a control group and an experimental group. The control group was given conventional treatment and the experimental group was given exercise rehabilitation in the hospital for 12 weeks to compare the indexes related to glucose and lipid metabolism and healthy fitness in the two groups.

RESULTS

After the intervention, the experimental group showed significant decreases in fasting blood glucose (FBG), glycated hemoglobin (HbA1c), insulin resistance index (HOMA-IR), triglycerides (TG), total cholesterol (TC), low-density cholesterol (LDL-C) and body fat percentage (p < 0.05), while high-density cholesterol (HDL-C), grip strength, lower limb extension, lower limb flexion, peak oxygen uptake were significantly higher (p < 0.05) and were more significant at 12 weeks compared to the 6-week intervention (p < 0.05). However, there were no significant changes in any of the glucose metabolism indicators in the control group before and after the intervention. A two-way repeated measures ANOVA showed that at control baseline levels, HbA1c decreased significantly in the experimental group after both 6 and 12 weeks of intervention compared to the control group (p < 0.05). After 6 weeks of intervention, the experimental group showed a significant decrease in body fat percentage and a significant increase in grip strength. After 12 weeks of intervention, the experimental group showed an increase in glycemic control from 33.3% to 73.3%, a significant decrease in body fat percentage and a significant increase in grip strength, lower limb extension and lower limb flexion strength and peak oxygen uptake.

CONCLUSION

In-hospital exercise rehabilitation can effectively improve the glycemic and lipid profiles of patients with T2DM combined with sarcopenia and enhance their health fitness, with good clinical rehabilitation effects.

Degenerative changes of the wrist in mixed martial arts and boxing based on the three column theory

OBJECTIVE

Mixed Martial Arts (MMA) is a relatively young combat sport. In contrast to classic boxing, MMA combines techniques of grappling and striking. However, characteristic long-term effects of MMA on the wrist are discussed controversially. Aim of this study was to elucidate characteristic degenerative changes of the wrist from MMA fighters in comparison to classic boxers.

METHODS

In this study, eleven professional MMA fighters and ten professional boxers with chronic wrist pain were examined and compared. Age, weight, number of fights and weekly hours of training were recorded. Wrist and hand of each fighter were examined using a 3T-MR scanner. Degenerations of the radial, central and ulnar column were analyzed according to Navarro's three-column theory and degenerative changes were categorized based on the classification of Fredericson.

RESULTS

There was no significant difference of age, weight and number of fights between MMA fighters and boxers (p > 0.15). However, MMA fighters practiced significantly more hours per week (19.5 (MMA) vs. 8.5 (boxing) hours/week, p < 0.001). No significant associations were found between different training times per Week in terms of degenerative changes of the wrist in MMA and boxing based on the three column theory. The comparison of degenerative changes in the columns between MMA and boxing showed no significant differences. The MRI showed a significantly higher degeneration in the radial column compared to the central column among MMA fighters for ligaments (p = 0.01) and bones (p = 0.03).

CONCLUSION

Due to different fighting techniques, different physical traumas, including falls, pattern of degenerations of the wrist between MMA fighters and boxers are different. MMA fighters suffer of a highly degenerative radial column and boxers suffer of a homogeneous degeneration of all three columns.

A physical fitness-evaluation system for outstanding Chinese male boxers

Background

We sought to create a system to evaluate the physical fitness of outstanding Chinese male boxers that included an evaluation index, fitness level criteria, and modeling. This system was then used to assess athletes' physical fitness and development.

Methods

Documentation, expert interviews, questionnaires, measurements, and statistical analyses were used in this study.

Results

The physical fitness evaluation system included the following three components: (1) body shape indexes (n = 4) including the backhand upper arm circumference differential, finger span height, Cottrell index, and pelvic width/shoulder width × 100; (2) body function indexes (n = 4) including relative maximum anaerobic power, relative maximal oxygen uptake, and creatine kinase and testosterone concentrations; and (3) athletic quality indexes (n = 9) including the speed strength index, the backhand straight punch strength, 3-min cumulative punching force, backhand straight punch reaction time, backhand straight punch speed, 30-m sprint, 9-min double shake jump rope, 1-min double shake jump rope, and sitting forward bend tests. A five-point grading system to evaluate physical fitness was established and an evaluation model was proposed.

Conclusions

The reference values were determined to be objective and effective using a back substitution process. Individual and differential assessments reflected the athletes' level of physical fitness. The critical values were established under the best and worst conditions and the optimal values were found to be valid and effective.

A comparative analysis of the physical fitness profile of Korean women's national amateur boxers by weight category

The purpose of this study was to examine the differences in specific physical fitness of the national amateur women's boxer. The Korean women's national amateur boxers were classified into the lightweight category (LWC, n=21) and middleweight category (MWC, n=13), and body composition (percentage body fat and body mass index) and specific physical fitness (maximal muscle strength, anaerobic power, isokinetic muscle strength, cardiopulmonary endurance) were measured. The Mann-Whitney U-test was conducted to determine the differences in the body composition and specific physical fitness in women's boxers. The percentage body fat (P=0.004) and body mass index (P<0.001) were significantly higher in the LWC compared to MWC. In addition, LWC showed significantly higher isokinetic muscle strength (P<0.001), upper anaerobic mean power (P=0.002), maximal muscle strength (P=0.003), and maximal heart rate at anaerobic threshold (P=0.029), maximal oxygen consumption (P<0.001) and the 20-m shuttle-run exercise (P=0.004) compared to MWC. In conclusion, the body fat percentage and body mass index levels among body composition were significantly higher in the MWC than in the LWC, and the constant muscle strength, maximum muscle strength, and cardiopulmonary endurance levels were significantly higher in the LWC than in the MWC. The results of this study are expected to provide useful data for planning future strategies for efficient and scientific training programs for each weight category.

Effects of Load and Focus of Attention on Mechanical Parameters During Bench-Press Throw in Resistance-Trained Men

PURPOSE

Power output is dependent on the load used during exercise such as bench-press throw (BPT). Attentional focus (external [EXT] vs internal [INT]) during exercise significantly modulates power performance. The purpose of the present study was to examine the effects of load and attentional focus on mechanical parameters during BPT.

METHODS

In a crossover study, 31 resistance-trained men (mean age 23.5 [3.0] y) performed BPT at 30% (light), 50% (moderate), and 70% (heavy) of 1-repetition maximum (1-RM) using an INT or EXT focus of attention in randomized order. A linear encoder was used to identify barbell vertical displacement, throw time, peak/average velocity, force, and power during the concentric lifting phase.

RESULTS

Statistical analysis revealed significant load × focus interaction effects for velocity and vertical displacement (P ≤ .045; 0.66 ≤ d ≤ 0.89). Post hoc analyses indicated significantly larger velocities and displacements at 30% and 70% of 1-RM in favor of EXT (P ≤ .038; 0.79 ≤ d ≤ 1.13) but similar values at 50% of 1-RM (P > .05). Furthermore, significant main effects of load were found for throw time, force, and power (P < .001; 4.20 ≤ d ≤ 14.0). While time and force gradually increased with higher loads (P < .001; 1.45 ≤ d ≤ 14.0), power output was larger at 50% compared with 30% and 70% 1-RM (P < .001; 3.09 ≤ d ≤ 7.07), irrespective of attentional focus.

CONCLUSIONS

The present findings indicated that practitioners may use EXT over INT attentional focus to enhance velocity and vertical displacement during BPT at light and heavy loads (ie, 30% and 70% 1-RM). At moderate loads (ie, 50% 1-RM), mechanical bench-press parameters appear to be less affected by attentional focus.

Cadet and Junior Performance Is Associated With Senior's World Championship and Olympics Achievement in Judo

Purpose: We determined whether cadet and junior Judo World Championship participation and medal achievement would predict senior performance at World Championship (WC) and Olympic Games (OG). Methods: We analyzed retrospectively a total of 7780 athletes who competed at the OG and WC in the cadet, junior, and senior between 2009 and 2021. Results: There was an increase in the probability of winning a medal in the senior category (WC and OG, and only WC) ranged from 4.3 to 4.5 for medal-winning cadets compared to non-medalists and this probability remained around 3.3-3.8 for medalists in the male and 5.3-5.4 for the female medalists in cadet WC. Moreover, the chance of winning a medal in the senior category (WC and OG) was 8.1-8.5 times greater for medalists when compared to non-medalists in the junior WC. In turn, the probability of winning a medal in the senior (WC) was 1.5-1.7 times greater for athletes who did not compete in the junior WC. In the OG, the probability of winning a medal was 3.5 greater times for medalists when compared to non-medalists at cadet and junior WC. Conclusion: Thus, being a cadet or junior WC medalist increases the probability of winning a senior WC or an Olympic medal.

Association of Genotype, High-G Tolerance, and Body Composition in Jet Aircraft Aviators

INTRODUCTION

Pilots of high-performance F15 and F16 jets must undergo periodic assessment of +8.5 Gz tolerance in a centrifuge, which is classified as a high-intensity exercise. Prior research has indicated that exercise performance may be correlated with alpha-actinin3 (ACTN3) and angiotensin-converting enzyme (ACE) genes, frequently termed the sports genes. This study aimed to investigate how ACTN3 and ACE genotypes correlate with high-g tolerance of Korean F15 and F16 pilots.

MATERIALS AND METHODS

A total of 81 Korean F15 and F16 pilots (ages 25-39 years) volunteered to participate in human centrifuge testing at +8.5 Gz. Exercise tolerance was calculated as the mean breathing interval during high-g tests, the target gene genotypes (ACTN3 and ACE) were identified, and body composition measurements were measured. The relationship among the ACTN3 and ACE genotypes, high-g tolerance, and body compositions were evaluated.

RESULTS

The ACTN3 genotypes identified included 23 RR (28.4%), 41 RX (50.6%), and 17 XX (21.0%). The ACE genotypes identified included 13 DD (16.0%), 39 DI (48.2%), and 29 II (35.8%). Both genes satisfied an equilibrium check. In multivariate analysis by Roy's max, the interaction of the target genes (ACTN3 and ACE) was significant (P < .05). The ACTN3 gene showed significance (P < .05), while ACE tended toward significance with a correlation of P = .057 with high-g tolerance(s). Body composition parameters including height, body weight, muscle mass, body mass index, body fat (%), and basal metabolic rate showed no significant correlation with either genotype.

CONCLUSION

In a preliminary study, the RR ACTN3 genotype showed a significant correlation with +8.5 Gz tolerance. Pilots with the DI genotype showed the highest high-g tolerance in this test; however, the test pass rate was higher in pilots with the DD genotype in the preliminary study. This result shows the possibility of test passing and tolerance superiority consisting of two different factors in the relationship between high-g tolerance and ACE genotype. This study showed that pilots with the RR + DI genotype had the highest high-g tolerance, which correlated with the presence of the R and D alleles of the ACTN3 and ACE genes, respectively. However, body composition parameters were not significantly correlated with genotype. These results could suggest a plural gene effect on high-g tolerance; further follow-up is required to determine the practical usage and applications of these results.

Concurrent Ingestion of Alkaline Water and L-Glutamine Enhanced Salivary α-Amylase Activity and Testosterone Concentration in Boxing Athletes

Athletes often take sport supplements to reduce fatigue and immune disturbances during or after training. This study evaluated the acute effects of concurrent ingestion of alkaline water and L-glutamine on the salivary immunity and hormone responses of boxers after training. Twelve male boxing athletes were recruited in this study. During regular training, the participants were randomly divided into three groups and asked to consume 400 mL of alkaline water (Group A), 0.15 g/kg body weight of L-glutamine with 400 mL of water (Group G), and 0.15 g/kg of L-glutamine with 400 mL of alkaline water (Group A+G) at the same time each day for three consecutive weeks. Before and immediately after the training, saliva, heart rates, and the rate of perceived exertion were investigated. The activity of α-amylase and concentrations of lactoferrin, immunoglobulin A (IgA), testosterone, and cortisol in saliva were measured. The results showed that the ratio of α-amylase activity/total protein (TP) significantly increased after training in Group A+G but not in Group A or G, whereas the ratios of lactoferrin/TP and IgA/TP were unaffected in all three groups. The concentrations of salivary testosterone after training increased significantly in Group A+G but not in Group A or G, whereas the salivary cortisol concentrations were unaltered in all groups. In conclusion, concurrent ingestion of 400 mL of alkaline water and 0.15 g/kg of L-glutamine before training enhanced the salivary α-amylase activity and testosterone concentration of boxers, which would be beneficial for post-exercise recovery.

The Effect of Post-Activation Potentiation Enhancement Alone or in Combination with Caffeine on Anaerobic Performance in Boxers: A Double-Blind, Randomized Crossover Study

Post-activation performance enhancement (PAPE) is a physiological phenomenon that refers to an acute excitation of the neuromuscular system following intense exercise that ends in enhanced physical performance in a subsequent bout of exercise. The scientific literature has primarily examined the effectiveness of PAPE alone or combined with caffeine (CAF) intake in all-out tests lasting ≤10 s, as the effect of PAPE is transitory. The aim of the present study was to determine the effect of a protocol to induce PAPE alone or in combination with caffeine intake on the 30 s Wingate Anaerobic Test in highly trained boxers. Twenty-five male and highly trained boxers (mean age: 20 ± 1 years) participated in a double-blind, randomized crossover study consisting of three different experimental conditions: (i) control (CON), with no substance intake and no PAPE protocol before the Wingate Anaerobic Test; (ii) PAPE + PLA, involving the intake of a placebo 60 min before and a PAPE protocol comprising a 10 s cycling sprint overloaded with 8.5% of the participants' body weight 10 min before the Wingate Anaerobic Test; and (iii) PAPE + CAF, involving the intake of 3 mg/kg of caffeine 60 min before and the same PAPE protocol used in the (ii) protocol before the Wingate Anaerobic Test. In all conditions, the participants performed the 30 s version of the Wingate Anaerobic Test with a load equivalent to 7.5% of their body weight, while the cycle ergometer setting was replicated. Immediately following the Wingate test, heart rate (HR), the rating of perceived exertion (RPE), and blood lactate concentration (Bla) were measured. In comparison to CON, PAPE + PLA enhanced mean power (p = 0.024; Effect size [ES] = 0.37) and total work (p = 0.022; ES = 0.38) during the Wingate test, accompanied by an increase in post-test blood lactate concentration (p < 0.01; ES = 0.83). In comparison to CON, PAPE + CAF enhanced mean power (p = 0.001; ES = 0.57), peak power (p = 0.013; ES = 0.57), total work (p = 0.001; ES = 0.53), post-test blood lactate concentration (p < 0.001; ES = 1.43) and participants' subjective perception of power (p = 0.041). There were no differences in any variable between PAPE + PLA and PAPE + CAF. In summary, a PAPE protocol that involves a 10 s all-out sprint 10 min before the Wingate Anaerobic Test was effective in enhancing Wingate mean power in highly trained boxers. The addition of 3 mg/kg of caffeine to the PAPE protocol produced an effect on mean power of a higher magnitude than PAPE alone, and it enhanced peak power along with participants' subjective perception of power. From a practical point of view, PAPE before exercise seems to be an effective approach for increasing Wingate performance in highly trained boxers, while the addition of caffeine can increase some benefits, especially peak power.

Effects of high-intensity functional training on physical fitness and sport-specific performance among the athletes: A systematic review with meta-analysis

OBJECTIVE

This study aims to meta-analyze the impact of high-intensity functional training on athletes' physical fitness and sport-specific performance.

METHODS

A systematic search was conducted in five well-known academic databases (PubMed, Scopus, Web of Science, EBSCOhost, and the Cochrane Library) up to July 1, 2023. The literature screening criteria included: (1) studies involving healthy athletes, (2) a HIFT program, (3) an assessment of outcomes related to athletes' physical fitness or sport-specific performance, and (4) the inclusion of randomized controlled trials. The Physical Therapy Evidence Database (PEDro) scale was used to evaluate the quality of studies included in the meta-analysis.

RESULTS

13 medium- and high-quality studies met the inclusion criteria for the systematic review, involving 478 athletes aged between 10 and 24.5 years. The training showed a small to large effect size (ES = 0.414-3.351; all p < 0.05) in improving upper and lower body muscle strength, power, flexibility, and sport-specific performance.

CONCLUSION

High-intensity functional training effectively improves athletes' muscle strength, power, flexibility, and sport-specific performance but has no significant impact on endurance and agility. Future research is needed to explore the impact of high-intensity functional training on athletes' speed, balance, and technical and tactical performance parameters.

Relationship between isokinetic strength of the knee joint and countermovement jump performance in elite boxers

Background

The lower limbs play a key role to develop the linear momentum for hitting power in effective boxing. The knee extensor and flexor strength guarantees the dynamic stability of boxers. The insufficient extensor strength of the lower extremities causes compensation during flexion resulting in movement errors or damage to knee joint muscles. This study was conducted to explore the isokinetic concentric strength of the knee flexor and extensor and the relationship between isokinetic knee extensors strength and countermovement jump (CMJ) performance in elite boxers.

Methods

Thirteen elite male boxers (Age: 25.15 ± 3.98 years, height 1.72 ± 0.04 m, weight 61.82 ± 10.46 kg, training years = 11.56 ± 2.67 years) performed the CMJ, and the isokinetic knee test was performed using the Biodex dynamometer.

Results

The maximal isokinetic peak torque of the knee extensor and flexor muscles was recorded at three angular velocities (60°/s, 180°/s, and 240°/s) on both sides of the legs. The relative peak value of torque in the knee extensors decreased significantly with increasing angular velocity. A difference in relative peak torque (RPT) was only seen at 60°/s in knee flexors. However, the H/Q ratio increased as the velocity increased from 60°/s to 240°/s (P < 0.05). The highest peak torque was found in the knee extensors at a velocity of 240°/s (r = 0.73, P < 0.001). The correlation between RPT and vertical jump height was the strongest at 240°/s. The strongest relationship was found between the height of the CMJ and the RPT of the deficit of knee extensors.

Conclusions

We suggest that explosive force training of the isokinetic muscles should be optimally carried out at a speed of 240°/s. The results of this study provide a reference for boxers to improve their jump height and lower-limb explosive strength through isokinetic strength training of the knee flexor and extensor.

Profiling the Physical Performance of Young Boxers with Unsupervised Machine Learning: A Cross-Sectional Study

Mexico City is the location with the largest number of boxers in Mexico; in fact, it is the first city in the country to open a Technological Baccalaureate in Education and Sports Promotion with a pugilism orientation. This cross-sectional study aimed to determine the physical-functional profile of applicants for admission to the baccalaureate in sports. A total of 227 young athletes (44F; 183M; 15.65 (1.79) years; 63.66 (14.98) kg; >3 years of boxing experience) participated in this study. Body mass (BM), maximal isometric handgrip (HG) strength, the height of the countermovement jump (CMJ), the velocity of straight boxing punches (PV), and the rear hand punch impact force (PIF) were measured. The young boxers were profiled using unsupervised machine learning algorithms, and the probability of superiority (ρ) was calculated as the effect size of the differences. K-Medoids clustering resulted in two sex-independent significantly different groups: Profile 1 (n = 118) and Profile 2 (n = 109). Except for BM, Profile 2 was statistically higher (p < 0.001) with a clear distinction in terms of superiority on PIF (ρ = 0.118), the PIF-to-BM ratio (ρ = 0.017), the PIF-to-HG ratio (ρ = 0.079) and the PIF-to-BM+HG ratio (ρ = 0.008). In general, strength levels explained most of the data variation; therefore, it is reasonable to recommend the implementation of tests aimed at assessing the levels of isometric and applied strength in boxing gestures. The identification of these physical-functional profiles might help to differentiate training programs during sports specialization of young boxing athletes.

Energy System Contributions during Olympic Combat Sports: A Narrative Review

This narrative review focuses on the studies that estimate the energy systems' contributions during match simulations of striking (boxing, karate, and taekwondo), grappling (judo), and weapon-based (fencing) Olympic combat sports. The purpose is to provide insights into the metabolism of these athletes. In striking Olympic combat sports, the oxidative contribution varied from 62% (in karate and taekwondo) to 86% (in boxing), the ATP-PCr system contribution varied from 10% (in boxing) to 31% (in taekwondo), and the glycolytic contribution was between 3% (in the third round of taekwondo) and 21% (in karate). In grappling combat sports, only judo was studied, and for a 4 min match, the oxidative contribution was 79%, followed by 14% ATP-PCr system contribution and 7% contribution from the glycolytic system. In fencing, the only weapon-based Olympic combat sport, the oxidative contribution varied from 81% (in the first bout) to 90% (in the second bout), followed by 9% (bout 2) to 12% (bout 1) contribution from the ATP-PCr system, and 0.6% to 7% contribution from the glycolytic system during 3 × 3 min bouts of épée match simulation. Hence, Olympic combat sports are primarily powered by the oxidative system, but the key scoring actions are likely fueled by anaerobic pathways.

Effects of Strength Training on Physical Fitness of Olympic Combat Sports Athletes: A Systematic Review

This review aimed to identify the effects of strength training programs on the physical fitness of Olympic combat sports (OCS) athletes. The systematic review included peer-reviewed articles that incorporated interventions that included pre- and post-intervention physical fitness assessment. The search was performed in the SCOPUS, PubMed, and Web of Science databases between April and September 2022. PRISMA and the TESTEX checklist were used to select and assess the methodological quality of the studies. Twenty studies with 504 participants (428 males and 76 females) were included. Significant improvements were found in athletes' maximal dynamic and isometric strength, muscle power, flexibility, and balance. In addition, improvements in favor of the training groups in specific actions of judo, karate, fencing, and boxing were observed. In conclusion, interventions aimed at the development of muscle strength in OCS, specifically in judo, boxing, karate, wrestling, and fencing, proved to be beneficial at a physical fitness level, resulting in significant increases in favor of the training groups with OCS, which could be used by trainers and coaches to improve the physical performance of athletes.

Variations in Power Performance and Perceptual Responses to Training in Olympic Boxers Over a 7-Month Training Period

PURPOSE

To assess the variations in power performance and perceptual training responses and compare the physical performance of national boxing athletes qualified or not qualified for the Tokyo Olympic Games over a 7-month training period.

METHODS

Twelve amateur boxers from the Brazilian national team were tested 6 times across 7 months. In the first assessment, boxers performed squat and countermovement jumps and bench press, prone bench pull, half squat, and jump squat power tests. In the following testing sessions, only countermovement jump and bench press power were assessed. In addition, the rating of perceived exertion and total quality recovery status were assessed in 106 training sessions across the study. Independent t test and repeated-measures analysis of variance were used for data analysis purposes.

RESULTS

No significant differences (P > .05) were observed between Olympic and non-Olympic groups for any test variables (effect size [95% CI] ranging from 0.01 [-1.13 to 1.13] to 0.69 [-0.53 to 1.79]). No significant changes (P > .05) were detected throughout the study for countermovement jump height and bench press power in either group (effect size [95% CI] ranging from 0.01 [-1.13 to 1.13] to 1.03 [-0.25 to 2.14]). Overall, both groups exhibited similar variations in both rating of perceived exertion and total quality recovery over the 7-month period.

CONCLUSIONS

Within the same national team, power-related performance was similar between Olympic and non-Olympic boxers. The maintenance of power abilities and optimization of technical and tactical skills seem to be key issues to consider during the final stages of preparation for international boxing competitions.

Relationships between isokinetic knee and shoulder peak strength with maximal punch force in boxing athletes

BACKGROUND: Muscle strength in the upper and lower limbs is a major contributing factor to punch force and is one of the keys to success in boxing. OBJECTIVE: This study aimed to investigate the relationship between knee and shoulder strength and punching force in boxers. METHODS: Twenty-one boxers completed knee flexion, knee extension, shoulder external rotation and internal rotation isokinetic concentric contractions at slow (60∘/s) and fast (180∘/s) angular velocities. Maximal punch force tests included lead and rear straight arm punching were assessed using a force platform. RESULTS: Pearson’s correlation coefficients revealed that knee extension (r= 0.646–0.848) and knee flexion (r= 0.470–0.646) peak torques were moderately to very strongly correlated with maximal punching force in lead and rear arms. The shoulder internal rotation (r= 0.492–0.634) and shoulder external rotation (r= 0.441–0.588) peak torques were moderate to strongly correlated with maximal punching force. Moreover, knee extension peak torques at 60∘/s had higher correlation with maximal punching force. In contrast, shoulder internal rotation peak torques at 180∘/s had a larger correlation with maximal punching force. CONCLUSIONS: The main findings indicated the importance of the capacity to generate maximum knee extension and rapid shoulder internal rotation strength, contributing to punch force production.

Comparison of Selected Characteristics of Slovak and Polish Representatives in Kickboxing

BACKGROUND

Previous kickboxing studies conducted over the last three decades have focused on improving performance through physical fitness characteristics; however, most of the research focused on men. The objective of this study is to assess the level of physical fitness of Slovak and Polish female kickboxers in the highest sport level as well as to compare the differences between them.

METHODS

The study included 20 female kickboxers on the highest level of sport performance, 10 from Slovakia (body mass-53.59; height-166.45) and 10 from Poland (body mass-60.35; height -169.95), from senior categories, with a mean age of 23 ± 2. The selection criteria included training experience and sports level. The level of physical fitness was evaluated by the following tests: Cooper's test, 50 m sprint, sit-ups, flexed arm hang and standing long jump. Technical and tactical indicators were used to assess the sports skill level during the competition.

RESULTS

The test results of both groups are very comparable based on the evaluated data of Kruskal-Wallis ANOVA. The attack activity index together with sit-ups demonstrated statistically significant differences (p < 0.05) between Slovak and Polish kickboxers. A strong positive correlation was proven between technical and tactical indicators and physical fitness tests in the results of both groups.

CONCLUSIONS

There exists a positive correlation between the technical and tactical indicators of kickboxers and the explosive strength of lower limbs, strength endurance, abdominal muscle strength, speed and aerobic endurance. Differences between Slovak and Polish kickboxers have been shown in the attack activity index and in the level of strength endurance. The level of speed and explosive power of the lower limbs was comparable in both groups of kickboxers.

Lower extremity isokinetic strength characteristics of amateur boxers

Aim: Sufficient strength and dynamic stability of the lower limbs are essential for improving punching force and preventing injury in amateur boxers. However, there are still no comprehensive reports on the isokinetic knee strength of boxers with different performance levels. The current study aimed to profile the isokinetic muscle strength of flexion and extension of the knee in boxers, as well as bilateral, unilateral, and functional ratios, and investigate the variation in these muscle strength characteristics associated with different performance levels.

Methods: Boxers were divided in two performance groups, elite (five males and four females) and non-elite groups (five males and four females). Muscle strength of the knee was determined via an IsoMed2000 device. Parameters examined included peak torque of the hamstring (H) and quadriceps (Q) during concentric (con) and eccentric (ecc) contractions at low (60°/S), medium (180°/S), and high (240°/S) speed and bilateral ratios (BLs), unilateral ratios (ULs), and functional ratios of dominant (D) and non-dominant limbs.

Results: In all angular velocities, the peak torque of H and Q was stronger in the elite group than in the non-elite group. ULs were lower in the elite group than in the non-elite group in Hcon/Qcon at 180D (p < 0.01) and 180ND (p < 0.05) and in Hecc/Qecc at 60D, 180D (p < 0.05) and 240D (p < 0.01). The elite group had higher BLs than the non-elite group in Hcon at 60°/S (p < 0.05) and Qcon at 180°/S (p < 0.05). The non-elite group had a higher functional ratio than elite boxers in Hecc/Qcon at 180D and 240D (p < 0.01).

Conclusion: Elite boxers had stronger knee strength in con and ecc contractions. All boxers had normal Hecc/Qecc and Hcon/Qecc. Hcon/Qcon and Hecc/Qcon were abnormal at lower angular velocity. Elite boxers had higher BLs and lower ULs, indicating that they are at a higher risk of injury.

Ten years of collecting hematological athlete biological passport samples—perspectives from a National Anti-doping Organization

The hematological module of the Athlete Biological Passport (ABP) aims to reveal blood doping indirectly by looking at selected biomarkers of doping over time. For Anti-Doping Organizations (ADOs), the ABP is a vital tool in the fight against doping in sports through improved target testing and analysis, investigations, deterrence, and as indirect evidence for use of prohibited methods or substances. The physiological characteristics of sport disciplines is an important risk factor in the overall risk assessment and when implementing the hematological module. Sharing of experiences with implementing the hematological ABP between ADOs is key to further strengthen and extend its use. In this study, we present 10 years of experience with the hematological ABP program from the perspectives of a National ADO with special attention to sport disciplines' physiological characteristics as a potential risk factor for blood doping. Not surprisingly, most samples were collected in sport disciplines where the aerobic capacity is vital for performance. The study highlights strengths in Anti-Doping Norway's testing program but also areas that could be improved. For example, it was shown that samples were collected both in and out of season in a subset of the data material that included three popular sports in Norway (Cross-Country Skiing, Nordic Combined, and Biathlon), however, from the total data material it was clear that athletes were more likely to be tested out of competition and on certain days of the week and times of the day. The use of doping control officers with a flexible time schedule and testing outside an athlete's 60 min time-slot could help with a more even distribution during the week and day, and thus reduce the predictability of testing. In addition to promoting a discussion on testing strategies, the study can be used as a starting point for other ADOs on how to examine their own testing program.

Effects of a Short-Term Heat Acclimation Protocol in Elite Amateur Boxers

ABSTRACT

Stone, BL, Ashley, JD, Skinner, RM, Polanco, JP, Walters, MT, Schilling, BK, and Kellawan, JM. Effects of a short-term heat acclimation protocol in elite amateur boxers. J Strength Cond Res XX(X): 000-000, 2022-Boxing requires proficient technical and tactical skills coupled with high levels of physiological capacity. Although heat and humidity negatively affect acute exercise performance, short-term exercise training in hot and humid environments can lead to physiological adaptations that enhance exercise performance in both hot and thermoneutral conditions. In highly trained endurance athletes, exercise-induced acclimation can occur in as little as 5 days (known as short-term heat acclimation [STHA]). However, the impact of a 5-day heat acclimation (5-DayHA) in combat athletes, such as elite amateur boxers, is unknown. The aim of the present investigation was to determine whether a 5-DayHA improves aerobic performance in a thermoneutral environment and causes positive physiological adaptations in elite boxers. Seven elite amateur boxers underwent a 5-DayHA protocol, consisting of 60-minute exercise sessions in an environmental chamber at 32 °C and 70% relative humidity. Repeat sprint test (RST) evaluated aerobic performance in a thermoneutral environment 24 hours before and after the 5-DayHA. Presession and postsession hydration status (urine specific gravity) and body mass were assessed. After a 5-DayHA period, boxers significantly improved RST performance (13 ± 7 to 19 ± 7 sprints, d = 0.92, p = 0.03) but not pre-exercise hydration status (1.02 ± 0.01 to 1.01 ± 0.01, d = 0.82, p = 0.07). Therefore, these findings suggest 5-DayHA enhances aerobic performance in elite-level amateur boxers and may provide a viable training option for elite combat athletes.

The Acute Physiological, Endocrine, Biochemical and Performance Responses Associated with Amateur Boxing: A Systematic Review with Meta-analysis

AbstractPrevious research has explored the demands of amateur boxing-specific activity; however, no holistic review of the acute responses to such activity currently exists. This systematic review aimed to provide a synthesis of the available literature on the acute physiological, endocrine, biochemical and neuromuscular responses to amateur boxing-specific activity. Following a search of EBSCOhost, SportDiscus, PubMed and Google Scholar databases, 25 studies were identified as meeting the inclusion criteria for the review. Methodological quality of the included studies were assessed via a modified Downs and Black checklist. Random-effects meta-analysis of standardised mean differences (SMD) revealed large (SMD = 4.62) increases in pre-post blood lactate (BLa), cortisol (SMD = 1.33), myoglobin (Mb) (SMD = 1.43) and aspartate transaminase (AST) (SMD = 1.37), in addition to moderate increases in creatine kinase (CK) (SMD = 0.65) and alanine aminotransferase (ALT) (SMD = 0.97). Small pre-post increases in counter-movement jump (CMJ) height (SMD = 0.33) were observed. Consistently greater pre-post alterations were observed in competitive bouts, followed by sparring, when compared with boxing-specific simulations. Considerable physiological, endocrine and biochemical responses are elicited following amateur boxing. Interestingly, neuromuscular and task-specific performance may not deteriorate following boxing-specific activity. The findings of the review may assist in the designing and periodising of boxing-specific training, dependent on the desired physical adaptations, training phase and recovery status of the amateur boxer.

Relationships Between Punch Impact Force and Upper- and Lower-Body Muscular Strength and Power in Highly Trained Amateur Boxers

ABSTRACT

Dunn, EC, Humberstone, CE, Franchini, E, Iredale, KF, and Blazevich, AJ. Relationships between punch impact force and upper- and lower-body muscular strength and power in highly trained amateur boxers. J Strength Cond Res 36(4): 1019-1025, 2022-This study examined the relationship between upper- and lower-body strength and power characteristics and punch performance in 28 highly trained male amateur boxers. Punch performance was assessed with a custom-built punch integrator using a 3-minute maximal effort punch test that contained straight- and bent-arm punches from the lead and rear hands. Peak punch force and force-time variables including impulse and rate of force development (RFD; calculated to various points) were assessed. Force, power, and RFD of the upper and lower body were assessed with countermovement bench throw, isometric bench push, countermovement jump (CMJ), and isometric midthigh pull (IMTP) tests. Correlation and regression analyses revealed significant (p < 0.05) relationships between peak punch force and forces measured in CMJ and IMTP tests. In addition, peak punch force was moderately and significantly correlated to body mass, but RFD in the lower body was not. Moreover, no meaningful relationships between punch performance characteristics and any upper-body strength or power parameter were identified. The results of this study show that lower-body strength but not RFD had a moderate to strong positive and significant correlation to peak punch force production. Although upper-body strength and power are expected to be important in boxing, they did not discriminate between boxers who punched with higher or lower peak force nor were they correlated to peak punch force. Training that improves lower-body strength without increasing total body mass (to maintain weight category) may positively influence punch capacity in highly trained amateur boxers.

Validity and reliability of impact forces from a commercially instrumented water-filled punching bag

Measuring striking forces is important to provide actionable insight for training and performance enhancement for combat sport athletes. Recent technology may provide a low-cost solution to an otherwise complicated kinetic assessment. The aim was to assess the reliability and validity of a water-filled training bag and integrated sensor for measuring peak impact force. A pendulum design was used to swing a range of known mass loads (kettlebells) from various heights to impact a stationary 21″ Aqua Training Bag®. For each condition, the momentum of the mass at impact was calculated and compared with the measured impact force from a pressure sensor affixed to the side of the water-filled bag. Peak impact force was strongly associated with calculated momentum (r(18) = 0.96 [0.91, 0.99], p < 0.001), with a high degree of shared variance (92.7%, F(1,18) = 229.9, p < 0.001). There was almost perfect agreement for all reliability loading conditions (ICC = 0.995–0.999) and typical error was ≤ 5% (CV = 3.3–5.1). Impact kinetics from the sensor appear to be reliable and valid and may be integrated into practice and research. However, the utility of the instrumented bag for striking kinetics of athletes, and thus practical utility when used in the field, requires further investigation.

Maximal isokinetic elbow and knee flexor-extensor strength measures in combat sports athletes: the role of movement velocity and limb side

Background

Maximal isokinetic strength ratios of joint flexors and extensors are important parameters to indicate the level of muscular balance at the joint. Further, in combat sports athletes, upper and lower limb muscle strength is affected by the type of sport. Thus, this study aimed to examine the differences in maximal isokinetic strength of the flexors and extensors and the corresponding flexor–extensor strength ratios of the elbows and knees in combat sports athletes.

Method

Forty male participants (age = 22.3 ± 2.5 years) from four different combat sports (amateur boxing, taekwondo, karate, and judo; n = 10 per sport) were tested for eccentric peak torque of the elbow/knee flexors (EF/KF) and concentric peak torque of the elbow/knee extensors (EE/KE) at three different angular velocities (60, 120, and 180°/s) on the dominant and non-dominant side using an isokinetic device.

Results

Analyses revealed significant, large-sized group × velocity × limb interactions for EF, EE, and EF–EE ratio, KF, KE, and KF–KE ratio (p ≤ 0.03; 0.91 ≤ d ≤ 1.75). Post-hoc analyses indicated that amateur boxers displayed the largest EE strength values on the non-dominant side at ≤ 120°/s and the dominant side at ≥ 120°/s (p < 0.03; 1.21 ≤ d ≤ 1.59). The largest EF–EE strength ratios were observed on amateur boxers’ and judokas’ non-dominant side at ≥ 120°/s (p < 0.04; 1.36 ≤ d ≤ 2.44). Further, we found lower KF–KE strength measures in karate (p < 0.04; 1.12 ≤ d ≤ 6.22) and judo athletes (p ≤ 0.03; 1.60 ≤ d ≤ 5.31) particularly on the non-dominant side.

Conclusions

The present findings indicated combat sport-specific differences in maximal isokinetic strength measures of EF, EE, KF, and KE particularly in favor of amateur boxers on the non-dominant side.

Trial registration: This study does not report results related to health care interventions using human participants and therefore it was not prospectively registered.

How Fit Are Special Operations Police Officers? A Comparison With Elite Athletes From Olympic Disciplines

The diverse tasks of special operations police (SOP) units place high physical demands on every officer. Being fit for duty requires a wide range of motor abilities which must be trained regularly and in a structured manner. But SOP operators have to plan and manage large proportions of their training alone, which makes it difficult to control. Therefore, this study aimed to highlight strengths and deficits of the SOP operators' fitness by comparing them to elite athletes, and to define future training goals. Retrospective data of 189 male SOP operators were used, who completed several isometric strength tests, a graded exercise test to determine maximal oxygen uptake, and countermovement jumps to determine leg muscle power. On the basis of a literature search, performance data were then compared to a total of 3,028 elite male athletes from 36 Summer Olympic disciplines. Pooled means and standard deviations were calculated for each discipline and effect sizes were used to analyze their similarities and differences to the SOP unit. On average, SOP operators were taller, heavier, and stronger than elite athletes. But both the ability to convert this strength into explosive movement and aerobic power was significantly less developed. From this point of view, SOP operators should consider polarized endurance training to work efficiently on improving aerobic performance. In addition, regular plyometric training seems necessary to improve leg muscle power and agility.

Evaluation of the Body Composition and Selected Physiological Variables of the Skin Surface Depending on Technical and Tactical Skills of Kickboxing Athletes in K1 Style

BACKGROUND

Kickboxing is a combat sport with high demands on fitness and coordination skills. Scientific research shows that kickboxing fights induce substantial physiological stress. Therefore, it is important to determine the body composition of athletes before competitions and to analyze the skin temperature and skin pH during the fight.

METHODS

This study aimed to determine the body composition, skin temperature, and skin pH in kickboxers during a fight according to K1 rules. A total of 24 kickboxers (age range: 19 to 28 years) competing in a local K1 kickboxing league participated in the present study.

RESULTS

Changes in skin temperature and pH were observed and significant correlations were found between body composition and weight category.

CONCLUSIONS

Changes in skin temperature and pH were demonstrated after each round of the bout. Level of body fat and muscle tissue significantly correlates with technical-tactical skills of the K1 athletes studied.

Associations between ACE Genotypes, +8.5 Gz Tolerance, and Body Composition in F-15 Pilot Candidates

INTRODUCTION

Pilots' +8.5Gz tolerance is related with their selection, safety and special mission suitability. The preliminary study about F-15 pilot candidates were rare, especially related with genetic effect like ACE (angiotensin converting enzyme) gene.

BACKGROUND

This study aimed to investigate the associations between the +8.5 Gz test qualification and angiotensin converting enzyme (ACE) genotypes in Korean F-15 pilot candidates for pilot special mission suitability and cadet body composition education.

MATERIALS AND METHODS

We performed +8.5Gz test (15 seconds), target gene (ACE) identified and body composition measurements from twenty Korean F-15 pilot candidates (ages 23.0-28.6 years). The +8.5Gz test results (pass and not-passed), body composition parameters and their relationship with the ACE genotype were evaluated.

RESULTS

Four (20%), six (30%), and 10 (50%) pilots had the DD, DI, and II genotypes based on the ACE gene identification results, respectively. Ten (50%) pilots passed by maintaining consciousness during the +Gz test. Of them, three (75%, 3/4), four (66.7%, 4/6), and three (30%, 3/10) had the DD, DI, and II genotypes (P < .05, DD > II), respectively. Compared with other genotypes, the DD genotype was associated with overall higher values of body composition indices, and this association was more prominent among pilots who passed the +8.5 Gz test.

DISCUSSION

In some ethnic groups, the DD genotype has been found to have an effect on elite players' high-intensity performance, including muscle power and strength. The DD genotype exhibited the highest performance in terms of passing rate, longest mean breathing interval(s), and higher values of body composition parameters in pilots who passed the +8.5 Gz test.

CONCLUSIONS

In this study, the group with the DD genotype exhibited a higher pass rate and heavier body composition parameters than the group with the II genotype. These results require further investigation to determine their significance and applicability in other ethnic groups.

The association between competitor level and the physical preparation practices of amateur boxers

Physical training, testing, and monitoring are three key constitutes of athlete physical performance; however, there is a currently a lack of information on the prevalence of such methods in amateur boxing. This study aimed to explore the physical preparation practices of senior elite (SEB) and senior development (SDB) amateur boxers, and to determine whether these practices were discriminated by competitor level. One hundred and one amateur boxers (SEB n = 59, SDB n = 42) were surveyed on their understanding, perceptions and application of physical training, monitoring, and testing practices. SEB were associated with strength/power training (SEB 78%, SDB 50%, P = 0.005), monitor of training intensities (SEB 68%, SDB 40%, P = 0.006), and performing regular fitness testing (SEB 76%, SDB 50%, P = 0.006), compared to SDB. Likewise, SEB were twice as likely (56%) to have their physical preparation managed by a strength and conditioning (S&C) coach or sport scientist, compared to SDB (26%; P = 0.005). For the first time, these data demonstrate the extent to which competitor level is associated with preparatory practices in amateur boxing. Cost was identified as the main barrier in implementing several forms of scientific support in SDB. These data serve as a framework to enhance preparatory practices across different competitor levels in amateur boxing. This might include boxer and coach education on the benefits to a more scientific approach, and the use of cost-effective methods to develop, monitor and assess amateur boxers physical performance. This may be of particular importance where boxers are not funded, such as the SDB in the current study. However, this work may also be used to emphasise the importance of strength/power training, physical fitness testing and monitoring at the elite level of amateur boxing.

Transference Effect of Short-Term Optimum Power Load Training on the Punching Impact of Elite Boxers

ABSTRACT

Loturco, I, Pereira, LA, Kobal, R, Fernandes, V, Reis, VP, Romano, F, Alves, M, Freitas, TT, and McGuigan, M. Transference effect of short-term optimum power load training on the punching impact of elite boxers. J Strength Cond Res 35(9): 2373-2378, 2021-This study examined the changes in bench press (BP), jump squat (JS), and half-squat (HS) power outputs induced by a short-term (1 week) training scheme based on the optimum power load (OPL) applied to national boxing athletes and measured the transference effect coefficient (TEC) of these exercises on punching impact. Eight elite boxing athletes from the Brazilian National team participated in this study. Athletes were tested before and after 3 power-oriented training sessions performed at the OPL. The physical assessments comprised punching impact measures (jabs and crosses) at fixed and self-selected distances, and bar-power output in BP, HS, and JS exercises. Magnitude-based differences were used to compare pre-training and post-training sessions. Transference effect coefficient was calculated as the ratio between the result gain in the "untrained exercises" (punching impact in jabs and crosses) and "trained exercises" (HS, JS, and BP), for variables presenting an effect size of at least 0.2. The OPL training elicited meaningful increases in the punching impact forces (∼8%) and in both JS and HS power outputs (∼12 and ∼14%, respectively), but not in BP power output. There was an effective transference (TEC = ∼0.80) of JS and HS performance gains to punching impact force, suggesting that increases in lower-limb power can be directly transferred to punching impact. These results provide coaches and practitioners with valuable information about how to rapidly and effectively increase the punching impact force of elite amateur boxers.

Effect of a Short HIIT Program with Specific Techniques on Physical Condition and Activity during Simulated Combat in National-Level Boxers

The present study investigated the effect of an additional short-duration HIIT program using boxing-specific techniques on activity during a simulated competition. Additionally, we investigated the impact on physical fitness, specifically aerobic performance and lower-body muscle power. Sixteen boxers were randomized into a control (n = 8) or experimental groups (n = 8). The experimental protocol consisted of 3 blocks of 5 repetitions of 30s all-out effort, with 6s recovery between repetitions and 1 min rest interval between blocks, conducted 3 days per week for 4 weeks. A two-way (group, two levels; moment, two levels) analysis of variance with repeated measurements in the second factor was used. For the experimental group, there was a change in body mass (ES = −0.13 (trivial)), body fat percentage (ES = −0.12 (trivial)), VO2max (ES = +0.42 (small)), CMJ (ES = +0.12 (trivial)), CMJ-left (ES = −0.11 (trivial)), CMJ-right (ES = +0.22 (trivial)), actions (ES = +0.68 (moderate)), time (ES = −0.29 (small)) and punches (ES = +0.56 (moderate)). For the control group, there was a change in body mass (ES = +0.04 (trivial)), body fat percentage (ES = −0.12 (trivial)), VO2max (ES = +0.11 (trivial)), CMJ (ES = −0.27 (small)), CMJ-left (ES = −0.39 (small)), CMJ-right (ES = +0.08 (trivial)), actions (ES = +0.08 (trivial)), time (ES = −0.65 (moderate)) and punches (ES = −0.57 (moderate)). The punches variable was significant concerning group-by-time interaction (F1,14 = 11.630; p = 0.004; n2 = 0.454). The present study indicated that the addition of a boxing-specific HIIT program is effective to increase the number of punches during a simulated match.

Variations in the Physical Performance of Olympic Boxers over a Four-Day National Qualifying Tournament

The aim of this study was to examine changes in body mass (BM) and power-related measures in Olympic boxers during an official qualifying boxing tournament. Fourteen elite amateur boxers from the Brazilian National Team (eight men and six women) participated in this study. Athletes performed three fights in four days against the same opponent of the same weight-category. Before and immediately after every fight, BM, countermovement jump (CMJ) height, and power production in the bench-press and half-squat exercises were assessed in the same order and on the same time of the day. A two-way repeated-measures ANOVA with the Bonferroni post-hoc analysis was used to determine the variations between pre- and post-measures. The statistical significance was set as p < 0.05. The athletes were able to maintain their baseline weight and physical performance throughout the experimental period, as shown by the lack of significant changes in BM, CMJ height, and upper- and lower-limb power output. Throughout a four-day qualifying tournament, the BM and power-related performance of Olympic boxers were not affected either by match execution or by successive matches. As scoring actions are highly dependent on muscle power, it is likely that these combat athletes are able to maintain optimal levels of performance across consecutive matches.

Enhanced structural connectivity within the motor loop in professional boxers prior to a match

Professional boxers train to reduce their body mass before a match to refine their body movements. To test the hypothesis that the well-defined movements of boxers are represented within the motor loop (cortico-striatal circuit), we first elucidated the brain structure and functional connectivity specific to boxers and then investigated plasticity in relation to boxing matches. We recruited 21 male boxers 1 month before a match (Time1) and compared them to 22 age-, sex-, and body mass index (BMI)-matched controls. Boxers were longitudinally followed up within 1 week prior to the match (Time2) and 1 month after the match (Time3). The BMIs of boxers significantly decreased at Time2 compared with those at Time1 and Time3. Compared to controls, boxers presented significantly higher gray matter volume in the left putamen, a critical region representing motor skill training. Boxers presented significantly higher functional connectivity than controls between the left primary motor cortex (M1) and left putamen, which is an essential region for establishing well-defined movements. Boxers also showed significantly higher structural connectivity in the same region within the motor loop from Time1 to Time2 than during other periods, which may represent the refined movements of their body induced by training for the match.

Physical Fitness and the Level of Technical and Tactical Training of Kickboxers

Background: Kickboxing is a dynamically progressing combat sport based on various techniques of punches and kicks. The high level of physical fitness underlies the optimal development of technique in the competitors. The objective of this study was the assessment of the level of fitness of kickboxers and the relationships between fitness and technical and tactical training. Methods: The study included 20 kickboxers aged 18–32 demonstrating the highest level of sporting performance. Their body mass ranged from 75 to 92 kg and their height from 175 to 187 cm. The selection of the group was intentional, and the criteria included training experience and the sports level assessed by the observation of the authors and opinion of the coach. The level of fitness was evaluated with the use of selected trials of International Committee on the Standardization of Physical Fitness Tests and Eurofit tests. Aerobic capacity was tested and indicators of efficiency, activeness and effectiveness of attacks were calculated. Results: A significant correlation between the indicators of technical and tactical training and results of fitness tests was shown. Conclusions: There exists a correlation between efficiency, activeness and effectiveness of attacks and the speed of upper limbs, explosive strength, static strength of a hand, agility, VO₂max and abdominal muscle strength.

The Test-Retest Reliability of Bilateral and Unilateral Force Plate-Derived Parameters of the Countermovement Push-Up in Elite Boxers

CONTEXT

Maximal power describes the ability to immediately produce power with the maximal velocity at the point of release, impact, and/or take off-the greater an athlete's ability to produce maximal power, the greater the improvement of athletic performance. In reference to boxing performance, regular consistent production of high muscular power during punching is considered an essential prerequisite. Despite the importance of upper limb power to athletic performance, presently, there is no gold standard test for upper limb force development performance.

OBJECTIVE

To investigate the test-retest reliability of the force plate-derived measures of countermovement push-up in elite boxers.

DESIGN

Test-retest design.

SETTING

High Performance Olympic Training Center.

PARTICIPANTS

Eighteen elite Olympic boxers (age = 23 [3] y; height = 1.68 [0.39] m; body mass = 70.0 [17] kg).

INTERVENTION

Participants performed 5 repetitions of countermovement push-up trials on FD4000 Forcedeck dual force platforms on 2 separate test occasions 7 days apart.

MAIN OUTCOME MEASURES

Peak force, mean force, flight time, rate of force development, impulse, and vertical stiffness of the bilateral and unilateral limbs from the force-time curve.

RESULTS

No significant differences between the 2 trial occasions for any of the derived bilateral or unilateral performance measures. Intraclass correlation coefficients indicated moderate to high reliability for performance parameters (intraclass correlation coefficients = .68-.98) and low coefficient of variation (3%-10%) apart from vertical stiffness (coefficient of variation = 16.5%-25%). Mean force demonstrated the greatest reliability (coefficient of variation = 3%). In contrast, no significant differences (P < .001) were noted between left and right limbs (P = .005-.791), or between orthodox or southpaw boxing styles (P = .19-.95).

CONCLUSION

Force platform-derived kinetic bilateral and unilateral parameters of countermovement push-up are reliable measures of upper limb power performance in elite-level boxers; results suggest unilateral differences within the bilateral condition are not the norm for an elite boxing cohort.

Biomechanical Analysis of the Cross, Hook, and Uppercut in Junior vs. Elite Boxers: Implications for Training and Talent Identification

Punching in boxing requires a combination of force and velocity of the acting arm, originating from an optimal synchronization of the different body segments. However, it is not well-understood what kinematic parameters of the punching execution influence boxing performance the most. This study aimed to investigate the differences in punching execution between 15 potential Olympic medalist boxers (Elite group) and 8 younger well trained boxers (Junior group). Each athlete was equipped with an instrumented suit composed of 17 inertial measurement units (IMU) and were asked to perform several series of 3 standardized punch types (cross, hook, and uppercut) with maximal force. Linear velocity, stability, and punch forces were computed from the different sensors. Our findings show that Elite boxers systematically produced more force and at a higher velocity for the three punch types compared to Juniors. Further analysis revealed differences in joint contributions between Elite and Juniors, Juniors presenting a higher contribution of the shoulder for the three punch types. Finally ground reaction force imbalance between the front and rear foot was revealed in the cross only, in all boxers (60.6 ± 24.9 vs. 39.4 ± 24.9% and 54.1 ± 7.1 vs. 45.9 ± 7.1%, p ≤ 0.05, for the front vs. rear foot in Elite and Juniors, respectively) but not different between groups. These results have important implications for practitioners involved in the talent identification process, longitudinal follow-up, and training of boxers.

The Effects of Intermittent Hypoxic Training on Anaerobic and Aerobic Power in Boxers

BACKGROUND

The aim of the study was to evaluate the effects of intermittent hypoxic training (IHT) on anaerobic and aerobic fitness in elite, national boxers.

METHODS

The study was conducted over a period of 6 weeks. It comprised 30 national championship boxers, divided into 2 groups: the experimental and control. Both groups performed the same boxing training twice a day (morning and afternoon training). In the afternoon, the experimental group performed training under normobaric conditions in a hypoxic chamber (IHT), while the control group undertook exercise in standard normoxic conditions. In both groups, before and after the 6-week programme, basic anthropometric indices as well as anaerobic (Wingate Test) and aerobic (graded test) fitness were assessed.

RESULTS

There was a significant increase in anaerobic peak power (988.2 vs. 1011.8 W), mean anaerobic power (741.1 vs. 764.8 W), total work (22.84 vs. 22.39 kJ), and a decrease in fatigue index (20.33 vs. 18.6 W·s-1) as well as time to peak power (5.01 vs. 4.72 s). Such changes were not observed in the control group. In both groups, no significant changes in endurance performance were noted after the training session - peak oxygen uptake did not significantly vary after IHT.

CONCLUSIONS

Our results have practical application for coaches, as the IHT seems to be effective in improving anaerobic performance among boxers.

Acute effects of high-intensity interval training on cognition and retinal microcirculation in experienced amateur boxers

BACKGROUND

Limited and contradictory data are available regarding the acute effects of endurance exercises on cognition and retinal microcirculation. Thus, we aimed to evaluate the acute effects of sport-specific high-intensity interval training (HIIT) on cognition and retinal vessel diameters in experienced amateur boxers.

METHODS

Eleven young (age 22.8±2.9 years) men with 10.7±4.8 years of boxing experience completed two sessions in random order: high-intensity intermittent punching load and passive rest. Cardiovascular response, retinal vessel diameters, and cognitive performance were evaluated at baseline, during exercise, and immediately after each session.

RESULTS

Increased heart rate during intermittent punching load (P<0.05) reaching 91.2±3.7% of the maximal heart rate was observed. The HIIT improved cognitive flexibility and inhibitory control (P<0.05), while the working memory and motor speed were not affected. Significant dilatation of temporal retinal venules (P<0.05) was observed after the HIIT compared with the values before the HIIT, resulting in a decreased arteriolar-to-venular diameter ratio (P<0.05).

CONCLUSIONS

At the functional level, an improvement in executive function due to intermittent high intensity punching load was observed, while at the physiological level, retinal venular dilatation was observed in experienced amateur boxers.

Kickboxers and crossfitters vertebral column curvatures in sagittal plane: Crossfit practice influence in kickboxers body posture

BACKGROUND

In combat sports, long-term training load can lead to sport-specific functional and body posture adaptations. The most often observed changes are in the shape of the anterior-posterior spinal curvatures. The abnormal inclination of the thoracic and lumbar regions of the spine may lead to an additional overload of the musculoskeletal system and spinal pain or decrease sports performance. Therefore it is crucial to prevent disadvantageous body posture features.

AIM

The aim was to examine differences in vertebral column's sagittal curves parameters between kickboxing fighters, kickboxing fighters who also trained CrossFit and CrossFit athletes and evaluate these parameters' predictive ability to predict sport disciplines. Received results show if CrossFit training influences vertebral column curvatures in the sagittal plane among Kickboxers is an effective method in proper body posture shaping.

METHODS

The study involved 45 men aged 25.2 years divided into three groups depending on the sport they practiced: group kickboxing (KB), kickboxing and CrossFit (KBCF), and CrossFit (CF). The body posture was observed using the photogrammetric method. The parameters of the sagittal plane were analyzed.

RESULTS

Among the kickboxers, it was observed that the angle of the thoracolumbar region, the angle of inclination of the thoracolumbar and lumbosacral regions significantly increased compared to other groups of athletes (p < 0.05).

CONCLUSION

Practicing kickboxing can be a factor in increasing the risk of postural defects. It was found that CrossFit training has a beneficial effect on the shape of physiological curvatures of the spine in combat sports athletes.

Evidence-based post exercise recovery in combat sports: a narrative review

INTRODUCTION

Some methods such as ergo nutritional aids, cooling or massage among others could improve recovery in combat sports (CS). The effects, doses, duration, and timing of these methods remains unknown. Nowadays, there is no clear consensus regarding the recovery strategies and it is necessary to understand the type of fatigue induced in CS and its underlying mechanisms. The main aim of this article is to review the update literature related to recovery strategies in CS.

EVIDENCE ACQUISITION

A literature search was conducted following preferred reporting items for review statement on the topic of: "combat sports," "recovery," "nutrition," "fatigue," "ergogenic aids," "weight cutting" and "hydration."

EVIDENCE SYNTHESIS

The initial search of the literature detected 369 articles about CS. Later, 307 were excluded after being determined unrelated to recovery or after failure to fulfill the inclusion criteria. Of the 80 included articles, 19 satisfied the final inclusion criteria.

CONCLUSIONS

To optimize CS performance, adequate recovery is required during training and competition processes. Traditional ergo nutritional supplementation of carbohydrates and proteins combined. Besides, the consumption of evidence supported supplementation (green tea, beetroot gels, creatine or alkaline water) improve recovery processes. Further methods of recovery including physical (cold water immersion, massage or photobiomodulation) and physiological (types of active recovery, sleep and rest) therapies have also been shown useful. This narrative review elucidates the important role of recovery techniques in CS.

Fusing Accelerometry with Videography to Monitor the Effect of Fatigue on Punching Performance in Elite Boxers

Wearable sensors and motion capture technology are accepted instruments to measure spatiotemporal variables during punching performance and to study the externally observable effects of fatigue. This study aimed to develop a computational framework enabling three-dimensional inverse dynamics analysis through the tracking of punching kinematics obtained from inertial measurement units and uniplanar videography. The framework was applied to six elite male boxers performing a boxing-specific punch fatigue protocol. OpenPose was used to label left side upper-limb landmarks from which sagittal plane kinematics were computed. Custom-made inertial measurement units were embedded into the boxing gloves, and three-dimensional punch accelerations were analyzed using statistical parametric mapping to evaluate the effects of both fatigue and laterality. Tracking simulations of a sub-set of left-handed punches were formulated as optimal control problems and converted to nonlinear programming problems for solution with a trapezoid collocation method. The laterality analysis revealed the dominant side fatigued more than the non-dominant, while tracking simulations revealed shoulder abduction and elevation moments increased across the fatigue protocol. In future, such advanced simulation and analysis could be performed in ecologically valid contexts, whereby multiple inertial measurement units and video cameras might be used to model a more complete set of dynamics.

Allometric Modeling of Wingate Test among Adult Male Athletes from Combat Sports

Background and objectives: Athletes from combat sports are grouped into a series of weight categories that are intended to promote fair competition. Differences in performance are partly attributable to differences in body size. Consequently, ratio standards in which a performance variable is simply divided by an anthropometric characteristic such as body mass are often used, although this application is not recommended. This study aimed to obtain allometric models to interpret Wingate Anaerobic Test (WAnT) outputs among male adult athletes from combat sports. Materials and Methods: The sample was composed of 64 participants aged 18–39 years (24.2 ± 4.6 years). Stature and body mass (BM) were measured and air displacement plethysmography used to estimate fat mass and fat-free mass (FFM). Lower-limb lean soft tissue (LL-LST) was derived from dual energy X-ray absorptiometry. WAnT outputs were peak power (WAnT-PP) and mean power (WAnT-MP). Allometric models were obtained from simple and multiple linear regressions using log-transformed variables. Results: Models derived from a single three-dimension descriptor explained a large portion of variance: WAnT-PP (BM: 31.1%; FFM: 54%; LL-LST: 47.2%) and WAnT-MP (BM: 50.1%; FFM: 57.4%; LL-LST: 62.7%). Finally, the best proportional allometric models emerged from the combination of LL-LST and FFM (WAnT-PP: 55%; WAnT-MP: 65%). Conclusions: The relationship between weight categories and performance did not seem to be explained by the basic principles of geometric similarity.

High-Intensity Interval Training Prescription for Combat-Sport Athletes

CONTEXT

Combat sports are composed of high-intensity actions (eg, attacks, defensive actions, and counterattacks in both grappling and striking situations depending on the specific sport) interspersed with low-intensity actions (eg, displacement without contact, stepping) or pauses (eg, referee stoppages), characterizing an intermittent activity. Therefore, high-intensity interval training (HIIT) is at the essence of combat-sport-specific training and is used as complementary training, as well. HIIT prescription can be improved by using intensity parameters derived from combat-sport-specific tests. Specifically, the assessment of physiological indexes (intensity associated with the maximal blood lactate steady state, maximal oxygen consumption, and maximal sprint) or of time-motion variables (high-intensity actions, low-intensity actions, and effort:pause ratio) is a key element for a better HIIT prescription because these parameters provide an individualization of the training loads imposed on these athletes.

PURPOSE

To present a proposal for HIIT prescription for combat-sport athletes, exemplifying with different HIIT protocols (HIIT short intervals, HIIT long intervals, repeated-sprint training, and sprint interval training) using combat-sport-specific actions and the parameters for the individualization of these protocols.

CONCLUSIONS

The use of combat-sport-specific tests is likely to improve HIIT prescription, allowing coaches and strength and conditioning professionals to elaborate HIIT short intervals, HIIT long intervals, repeated-sprint training, and sprint interval training protocols using combat-sport actions, providing more specificity and individualization for the training sessions.

DOES PRE-COMPETITIVE ANXIETY INTERFERE IN THE PERFORMANCE OF BOXING ATHLETES IN BRAZIL? A PILOT STUDY

ABSTRACT Introduction: Pre-competitive anxiety is one of the psychological factors that can greatly influence athletes' performance, especially when it comes to individual sport like boxing. Objective: To analyze the level of pre-competitive anxiety in male athletes in the adult and young adult categories, and their correlation with the final results of the last Brazilian National Championship. Methods: A total of 60 young adult athletes participated in the study: 38 non-medalists (17.17±0.54 years and 66.38±13.21 kg) and 22 medalists (17.48±0.54 years and 66.21±12.96 kg). The “adults” group consisted of 35 athletes: 11 non-medalists (22.60±4.65 years and 68.33±14.08 kg) and 24 medalists (22.60±4.82 years and 67.33 ±13.13 kg). Results: The levels of cognitive anxiety in the young adult athletes group presented significant differences: medalists presented lower scores than non-medalists (12.77±2.62 and 15.92±5.20, respectively). In the adults group, medalists presented higher scores than non-medalists (15.23±4.42 and 12.00±4.11). Significant differences were observed in somatic anxiety levels between the young adult medalists and the other groups (p = 0.038). In addition, levels of self-confidence were high in all groups (young adult non-medalists = 29.42±4.82; adult non-medalists = 26.14±4.94, young adult medalists = 31.59±4.24 and adult medalists = 28.91±4.88). Conclusion: We conclude that self-confidence may interfere with anxiety levels, considering that medal-winning boxers are less prone to cognitive anxiety than non-medalists, and that both groups have high levels of self-confidence. Level of evidence I; High quality randomized trial with statistically significant difference or no statistically significant difference but narrow confidence intervals.