ObjectiveTo characterise the time course of changes in haemoglobin mass (Hbmass) in response to altitude exposure.MethodsThis 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.ResultsDuring-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%.ConclusionsCamps as short as 2 weeks of classic and LHTL altitude will quite likely increase Hbmass and most athletes can expect benefit.
Measurement of punch performance in a reliable, quantitative manner is relevant to combat sport, military, and concussion research. A punching protocol (3MPT) was developed, based on performance demands of amateur boxing, and evaluated on a custom‐built punch integrator (PI). PI reliability and accuracy were assessed by calculating TE and CV for a range of known masses. A within‐subject, repeated‐measures design assessed the test‐retest reliability of 3MPT. Fifteen male boxers (17.5 ± 0.5 years; 177.5 ± 9.5 cm; 73.0 ± 14.0 kg) were familiarized and then completed two 3MPT trials 90 minutes apart on 2 days (total of four tests). Peak punch force (N), relative punch force (N/kg), impulse (N·s), and rate of force development calculated to various time points were compared using a linear mixed model. Smallest worthwhile change (SWC) was also computed. PI data were reliable and accurate (CV <0.1%). TE and SWC comparisons revealed that 3MPT can detect moderate and large changes in performance; however, within‐day reliability improved from day 1 (3.1%‐13.8%) to 2 (2.3%‐5.1%) indicating a possible learning effect. Likewise, differences between test one and two were greater on day 1 than 2. Numerous punch‐related variables can be accurately and reliably measured using the 3MPT but repeat‐trial familiarization is suggested to reduce between‐test variability.
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.
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.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.