The effect of fatiguing lower-body exercise on punch forces in highly-trained boxers.

This study aimed to examine the effect of intense intermittent lower-body and trunk exercise (rowing) on punching performance in 28 highly-trained male amateur boxers. Straight- and bent-arm punch performances were assessed with a custom-built punch integrator using a 3-min maximal-effort punch test, completed in both non-fatigued (ROWpre) and fatigued (ROWpost) states. A within-subject repeated measures design was implemented; subjects completed ROWpre, then 9 × 1-min bouts of rowing (1-min rest intervals), followed by ROWpost. Peak punch force and force-time variables, including impulse and rate of force development (RFD; calculated to five time points), were assessed. Differences between ROWpre and ROWpost for each punch type (jab, cross, lead- and rear-hand hook) were tested with a linear mixed model, and effect sizes (Cohen's d) were calculated. Results showed significant (p < 0.05) reductions in punch force in ROWpost compared to ROWpre for all punch types as well as significant delays in the time to reach specific force levels, and relative percentages of peak force (RFD) in all punches except the jab. It is likely that fatigue of the lower body and trunk muscles impaired ground reaction force, and thus punch force, production. This effect was larger in punches that involved a greater degree of trunk rotation, crosses and hooks, than in the jab which relies predominantly on arm extension. These findings reveal the negative effect of fatigue on punch force production, and provide evidence that lower-body and trunk force are important for generating punch force. HighlightsThe ability of the lower body to generate force affects the magnitude of punch force produced in trained boxers.A bout of intense rowing exercise significantly reduces punch force, and rate of force development. This should be carefully considered when programming and scheduling boxing specific training sessions and strength and conditioning sessions.While non-specific fatigue affected the punch performance of boxers, the authors call for further research to examine the effects of fatigue sustained during a boxing bout in comparison to non-boxing muscular fatigue and a non-exercise control.

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.

Understanding the "gut instinct" of expert coaches during talent identification.

Coaches are an integral part of talent identification in sport and are often used as the "gold standard" against which scientific methods of talent identification are compared. However, their decision-making during this process is not well understood. In this article, we use an ecological approach to explore talent identification in combat sports. We interviewed twenty-four expert, international-level coaches from the Olympic disciplines of boxing, judo, and taekwondo (age: 48.7 + 7.5 years; experience: 20.8 + 8.3 years). Findings indicated that when coaches identify talent they rely on "gut instinct": intuitive judgements made without conscious thought, used to direct attention to particular athletes or characteristics. Our analysis revealed four major contributors to coaches' intuition: experiential knowledge, temporal factors, seeing athletes in context, and what can be worked with. Our findings demonstrate that i) athlete selections may be influenced by the coaches' perceived ability to improve certain athletes (rather than solely on athlete ability); and ii) "instinctual" decisions are the result of years of experience, time spent with the athlete, and the context surrounding the decision. Based on these findings, we recommend that future research focuses on the duration and conditions that are required for coaches to confidently and reliably identify talented athletes.

Pilot Study on the Reliability of the Coach's Eye: Identifying Talent Throughout a 4-Day Cadet Judo Camp.

A typical assumption found in talent identification literature is that different coaches, given the same athletes and circumstances, will identify the same subset of athletes as "talented". However, while coaches play a major role during talent identification in practical sport settings, there is limited empirical research exploring the processes which underpin this. The purpose of this study was to explore the reliability of "the coach's eye" during the assessment of talent in a group of athletes. Specifically, this project compared inter-coach agreement between nine judo coaches (ages 35.8 ± 10.6 years) with varying levels of experience (12.9 ± 8.9 years) in the evaluation of 24 talented cadet judo athletes (13-15 years) at seven timepoints throughout a 4-day development training camp. Without discussion of their scores with other coaches, coaches provided a single score representing each athlete's "potential for future performance" on an 11-point Likert scale at each timepoint. Scores from each coach were converted into rankings from 1 to 24 to create a normalized scale to facilitate comparison of athletes. Based on their rankings at each timepoint, athletes were placed into one of three evenly distributed groups (high, medium, and low rank). Inter-coach agreement at each timepoint was determined by the number of coaches who ranked each athlete in the same group, categorized at three levels: 50, 75 or 100% agreement. Overall results showed that at completion of the camp, coaches reached 100% agreement on only two athletes, both of whom were in the high rank group. When inter-coach agreement was set at 50%, 15 athletes (62.5%) were placed into like groups. The first timepoint at which coaches were able to differentiate between the majority of athletes was Timepoint 3 (end of day 2). The findings suggest that, in isolation, coaches do not agree on the talent or potential of athletes. This indicates that the "coach's eye" is subjective and variable, and, given the same context, there is poor inter-coach agreement in the identification of talented athletes. In turn, these findings may have significant implications for both future talent identification research and athlete selection processes by sport organizations.

Coach knowledge in talent identification: A systematic review and meta-synthesis.

OBJECTIVES: Talent identification traditionally relies on the knowledge and perceptions of expert coaches to identify and predict potential future elite athletes. Experiential coach knowledge is a valuable source of information to guide research in this ill-defined and under-researched area. This review aims to synthesize current empirical understanding of coach knowledge as it relates to decision making in talent identification. DESIGN: This systematic review and meta-synthesis used the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to identify relevant literature. METHODS: Eligible studies were critically appraised for quality, and key findings from the 14 studies were integrated to allow for thematic analysis. RESULTS: The meta-synthesis revealed the key theme of 'instinct' as the primary contributor to coach decisions during talent identification. Subordinate themes informing coach instinct were 'drive and ambition', 'game intelligence' and 'physical and technical skills'. CONCLUSIONS: Coaches appear to make decisions about talent based on their tacit knowledge or instinct. Understanding how coaches develop these instinctual 'feelings' may guide future research into talent identification and enhance our understanding of how experiential coach knowledge is developed and utilised in the daily training environment.

Effects of Different Fatigue Levels on Physiological Responses and Pacing in Judo Matches.

Franchini, E, Takito, MY, Alves, ED, Shiroma, SA, Julio, UF, and Humberstone, C. Effects of different fatigue levels on physiological responses and pacing in judo matches. J Strength Cond Res 33(3): 783-792, 2019-The objective of this study was to compare athletes' pacing during judo match simulation between different fatigue states. Twelve judo athletes (30.2 ± 3.2 years old, 85.6 ± 10.8 kg, 181.0 ± 5.7 cm, 19 ± 7 years of judo experience) completed three 4-minute matches against the same opponents, at 15-minute intervals in 3 different conditions: after warm-up (Control; C); after a regular training session (totaling 90 minutes); after a high-intensity interval exercise (2 blocks of 10 sets of 20-second all-out uchi-komi, with 10-second interval between sets and 5-minute interval between blocks). All matches were mediated according to the official rules, filmed, and analyzed concerning: rating of perceived recovery (RPR), rating of perceived exertion (RPE), heart rate (before and after match), blood lactate concentrations [La] before, peak after match and delta (peak minus the prematch values), and time-motion measures (frequencies and durations of actions). Time-motion measures included athlete displacement without contact, gripping, attack, feint, groundwork combat, pauses, and high- to low-intensity effort ratio. The experimental conditions resulted in different physiological and perceived responses prematch (HR, [La], RPR) and postmatch simulations (HR and [La]peak), with no change in RPE and few changes in technical variables. There was a decrease in grip dispute time, and increase in time of displacement without contact. These technical changes were enough to preserve the pace during the matches, which seemed to be controlled by the athletes to maintain their number of attacks, feints, and RPE.

Training to Compete at Altitude:Natural Altitude or Simulated Live High:Train Low?

PURPOSE: To compare the effects of natural altitude training (NAT) and simulated (SIM) live high:train low altitude training on road-race walking performance (min), as well as treadmill threshold walking speed (km·h-1) at 4 mmol·L-1 and maximal oxygen consumption, at 1380 m. METHODS: Twenty-two elite-level male (n = 15) and female (n = 7) race walkers completed 14 d of NAT at 1380 m (n = 7), SIM live high:train low at 3000:600 m (n = 7), or control conditions (600-m altitude; CON, n = 8). All preintervention and postintervention testing procedures were conducted at 1380 m and consisted of an incremental treadmill test, completed prior to a 5 × 2-km road-race walking performance test. Differences between groups were analyzed via mixed-model analysis of variance and magnitude-based inferences, with a substantial change detected with >75% likelihood of exceeding the smallest worthwhile change. RESULTS: The improvement in total performance time for the 5 × 2-km test in NAT was not substantially different from SIM but was substantially greater (85% likely) than CON. The improvement in percentage decrement in the 5 × 2-km performance test in NAT was greater than in both SIM (93% likely) and CON (93% likely). The increase in maximal oxygen consumption was substantially greater (91% likely) in NAT than in SIM. Improvement in threshold walking speed was substantially greater than CON for both SIM (91% likely) and NAT (90% likely). CONCLUSIONS: Both NAT and SIM may allow athletes to achieve reasonable acclimation prior to competition at low altitude.

Human behaviours associated with dominance in elite amateur boxing bouts: A comparison of winners and losers under the Ten Point Must System.

Humans commonly ascertain physical dominance through non-lethal fighting by participating in combat sports. However, the behaviours that achieve fight dominance are not fully understood. Amateur boxing competition, which is judged using the subjective "Ten Point Must-System", provides insight into fight dominance behaviours. Notational analysis was performed on 26 elite male competitors in a national boxing championship. Behavioural (guard-drop time; movement style [stepping/bouncing time]; clinch-time; interaction-time) and technical (total punches; punches landed [%Hit]; air punches [%Air]; defence) measures were recorded. Participants reported effort required (0-100%) and perceived effect of fatigue on their own performance (5-point Likert scale) following bouts. Differences between winners and losers, and changes across the duration of the bout were examined. Winners punched more accurately than losers (greater %Hit [33% vs. 23%] and lower %Air [17% vs. 27%]) but total punches, defence and interaction-time were similar. From rounds 1-2, clinch-time and guard drops increased whilst bouncing decreased. Perceived effect of fatigue increased throughout the bout while perceived effort increased only from rounds 2-3. %Hit and movement index together in regression analysis correctly classified 85% of bout outcomes, indicating that judges (subjectively) chose winning (dominant) boxers according to punch accuracy and style, rather than assertiveness (more punches thrown). Boxers appear to use tactical strategies throughout the bout to pace their effort and minimise fatigue (increased guard drops, reduced bouncing), but these did not influence perceived dominance or bout outcome. These results show that judges use several performance indicators not including the total number of successful punches thrown to assess fight dominance and superiority between fighters. These results provide valuable information as to how experienced fight observers subjectively rate superiority and dominance during one-on-one human fighting.

Altitude training and haemoglobin mass from the optimised carbon monoxide rebreathing method determined by a meta-analysis.

OBJECTIVE: To characterise the time course of changes in haemoglobin mass (Hbmass) in response to altitude exposure. METHODS: This meta-analysis uses raw data from 17 studies that used carbon monoxide rebreathing to determine Hbmass prealtitude, during altitude and postaltitude. Seven studies were classic altitude training, eight were live high train low (LHTL) and two mixed classic and LHTL. Separate linear-mixed models were fitted to the data from the 17 studies and the resultant estimates of the effects of altitude used in a random effects meta-analysis to obtain an overall estimate of the effect of altitude, with separate analyses during altitude and postaltitude. In addition, within-subject differences from the prealtitude phase for altitude participant and all the data on control participants were used to estimate the analytical SD. The 'true' between-subject response to altitude was estimated from the within-subject differences on altitude participants, between the prealtitude and during-altitude phases, together with the estimated analytical SD. RESULTS: During-altitude Hbmass was estimated to increase by ∼1.1%/100 h for LHTL and classic altitude. Postaltitude Hbmass was estimated to be 3.3% higher than prealtitude values for up to 20 days. The within-subject SD was constant at ∼2% for up to 7 days between observations, indicative of analytical error. A 95% prediction interval for the 'true' response of an athlete exposed to 300 h of altitude was estimated to be 1.1-6%. CONCLUSIONS: Camps as short as 2 weeks of classic and LHTL altitude will quite likely increase Hbmass and most athletes can expect benefit.