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Predictors of performance in Amateur Olympic distance triathlon
Abstract
Objective:
Present study examines predictors of the overall race time and disciplines in the Olympic distance triathlon.
Methods:
Thirty-nine male and six female triathletes were evaluated for anthropometric, physiological, genetic, training, clinical and circadian characteristics. Body composition, maximum capacity for oxygen uptake (V˙O2max), maximum aerobic velocity (MAV), anaerobic threshold (AT), triathlon experience (TE) and XX genotype for α-actinin 3 affected total race time (p<0.05).
Results:
Total race time can be predicted by MAV (ß = -0.430, t = -3.225, p = 0.003), TE (ß = -0.378, t = -3.605, p = 0.001), and percentage of lean mass (%LM) (ß = -0.332, t = -2.503, p = 0.017). Swimming can be predicted by MAV (ß = -0.403, t = -3.239, p = 0.002), TE (ß = -0.339, t = -2.876, p = 0.007), and AT%V˙O2max (ß = 0.281, t = 2.278, p = 0.028). Cycling can be predicted by MAV (ß = -0.341, t = -2.333, p = 0.025), TE (ß = -0.363, t = -3.172, p = 0.003), and %LM (ß = -0.326, t = -2.265, p = 0.029). In running split, MAV (ß = -0.768, t = -6.222, p < 0.001) was the only parameter present in the best multiple linear regression model.
Conclusion:
The most important variables in multiple regression models for estimating performance were MAV, TE, AT and %LM.
... The variables associated with triathlon performance have previously been studied. Therefore, prediction equations for triathlon performance have also been developed; however, previous studies have only included male athletes, or when female athletes were included, the sex was not evaluated as a biological variable [9,10]. The knowledge of the main predictive variables of performance for each sex separately, can help coaches in directing the training sessions to obtain adaptive responses of the most important predictive variables of performance and optimize the improvement of sports performance. ...
... The G*Power version 3.1.9.2 (Franz, Universität Kiel, Germany) was used to determine the sample size and analyze the test power level. A sample size calculation for regression analysis for overall race time with two predictors, using previous published data from Puccinelli et al. [10] (r 2 = 0.607), showed that 20 athletes were needed to detect a relevant difference with 80% power and a significance level of 5%. The powers of the analyses were also calculated. ...
... Although the literature agrees that men have higher maximum oxygen consumption values [8], data on VTs are contradictory. Puccinelli et al. [10] discovered that female athletes had a higher percentage ofVO 2 max at VT and RCP than male athletes. These contradictory findings could be attributed to the varying levels of training of the athletes. ...
Citation: Barbosa, J.G.; de Lira, C.A.B.; Vancini, R.L.; dos Anjos, V.R.; Vivan, L.; Seffrin, A.; Forte, P.; Weiss, K.; Knechtle, B.; Andrade, M.S. Abstract: The purpose of this study was to verify the physiological and anthropometric determinants of triathlon performance in female and male athletes. This study included 40 triathletes (20 male and 20 female). Dual-energy X-ray absorptiometry (DEXA) was used to assess body composition, and an incremental cardiopulmonary test was used to assess physiological variables. A questionnaire about physical training habits was also completed by the athletes. Athletes competed in the Olympic-distance triathlon race. For the female group, the total race time can be predicted byVO 2 max (β = −131, t = −6.61, p < 0.001), lean mass (β = −61.4, t = −2.66, p = 0.018), and triathlon experience (β = −886.1, t = −3.01, p = 0.009) (r 2 = 0.825, p < 0.05). For the male group, the total race time can be predicted by maximal aerobic speed (β = −294.1, t = −2.89, p = 0.010) and percentage of body fat (β = 53.6, t = 2.20, p = 0.042) (r 2 = 0.578, p < 0.05). The variables that can predict the performance of men are not the same as those that can predict the triathlon performance of women. These data can help athletes and coaches develop performance-enhancing strategies.
... Sport-specific technical skills assessments have been demonstrated a great sensitivity to discriminate different competitive levels and predict future sports performance in the talent identification area [42]. The present multidimensional proposal is based on a MLR analysis and has been previously applied to predict or explain sports performance, both in individual sports, such as swimming [43], triathlons [44], or artistic gymnastics [45], and in team sports, such as field hockey [46], handball [17,47], volleyball [48], or soccer [49][50][51]. However, its practical application in team sports is more complex, due to the necessary configuration of a ranking which acts as a response or dependent variable in MLR analysis, and which in many individual sports is already established by its own rules and regulations (e.g., ATP ranking in tennis, FINA points in swimming, ITRA points in trail running, etc.). ...
Sports performance is a complex process that involves many factors, including ethnic and racial differences. China’s youth soccer is in a process of constant development, although information about the characteristics of its players and their methodological systems is scarce. The aim of this retrospective study was to characterize the physical fitness and the competitive performance of 722 Chinese players of three sports categories (8.0–9.9, 10.0–11.9 and 12.0–13.9 years), who were classified by their coaches as talented (n = 204) or untalented (n = 518). Players were assessed for anthropometry (body height, body mass, body mass index), lung capacity (Forced Vital Capacity), jumping performance (Squat Jump, Countermovement Jump and Abalakov tests), sprinting performance (10 m and 30 m Sprint tests), agility performance (Repeated Side-Step test) and flexibility (Sit & Reach test). A descriptive, comparative, correlational and multivariate analysis was performed. Competitive ranking was created in order to act as dependent variable in multiple linear regression analysis. Results indicate that Chinese players classified as talented have better motor performance than untalented ones. However, these differences are neither related nor determine the competitive performance of one group or the other.
... This was largely due to the improvement in movement biomechanics and body composition. Puccinelli et al. [27] showed that body composition (as well as previous experience and aerobic capacity) is a good predictor for Olympic triathlon-distance performance in amateurs. Similar results were noted by other authors in various disciplines [28,29]. ...
Monitoring the training of amateur long-distance crosscountry skiers (XCS) can help ath-letes' achieve a higher exercise capacity and protect their health. The aim of this study was to assess body composition changes and lipid profiles in middle-aged amateur long-distance XCS after four months of training, including specialized roller ski training. The results of the time-to-exhaustion (TTE) test and blood tests and changes in body composition were analyzed with basic descriptive statistics: the paired Wilcoxon test was used to compare the results (initial and final). Spearman's rank correlation coefficient (R) was used to assess the influence of various variables on maximum oxygen uptake (VO2max). The findings show that training of amateur long-distance XCS improved maximal oxygen uptake (p = 0.008) and had a positive effect on fat reduction, measured in percentages (p = 0.038) and in kilograms (p = 0.023), but did not change blood lipids or other parameters. Further research could focus on other aspects of the annual training cycle: the competition period, and women in a larger group of athletes. Training with roller skis and a crosscountry skiing training machine (a specialized machine for strengthening the arms and upper body) can support health and prevent obesity, overweight, and cardiovascular disease.
... The subjects constituted the same population of the athletes studied in Puccinelli et al. 19 , a previous study about the best predictors for Olympic distance triathlon performance. least one year of triathlon practice, and with medical approval for the maximum effort. ...
Background: Endurance sports are strongly associated with maximum oxygen uptake, anaerobic threshold, running economy and body fat percentage. Despite the importance for performance of the low-fat mass being a consensus in the literature, there are no data about the importance of the pattern of fat distribution. Therefore, the aim of the present study was to investigate the association between fat mass distribution with triathlon performance and physiological determinants of performance: maximal oxygen consumption (VO2max), ventilatory threshold (AT) and running economy (RE), and to verify the predictive value for performance of gynoid or android fat mass distribution.
Methods: Thirty-nine triathletes (38.8±6.9 years, 174.8±6.5cm and 74.3±8.8kg) were evaluated for anthropometric (total body mass, fat mass, lean mass, android and gynoid fat mass) and physiological (VO2max, AT and RE) parameters. Split and overall race times were registered.
Results: Overall race time relationship with gynoid fat mass (r=.529, p<.05) was classified as moderate higher than and with android fat mass (r=.416, p<.05) was classified as low. All split times and overall race time presented significant positive correlation with only total fat mass (%) (r =.329 to .574, p<.05) and with gynoid fat mass (%) (r=.359 to .529, p<.05). Overall race time can be better predicted by gynoid fat mass (ß=0.529, t=4.093, p<0.001, r2=0.28) than by android fat mass (ß =0.416, t=2.997, p=0.005, r2=0.17).
Conclusions: Fat mass distribution is associated with triathlon performance, and the gynoid fat pattern is worse for triathlon performance than the android pattern.
The capacity of laboratory tests to predict competition performance has been broadly researched across several endurance sports. The aim of the present study was to analyse how pool swimming performance can predict the result of the swimming segment in triathlon competitions and compare predictability differences based on competition level and distance. Eighteen male triathletes participated in the study. Three were ranked world-class, ten elite/international level, and five highly trained/national level. A total of sixty-one graded multi-stage swimming tests were conducted. Blood lactate was measured to calculate the following hypothetical predictor variables: speed at lactate threshold 1 (LT1), speed at lactate threshold 2 (LT2), and speed in the last repetition of the test (S L200). The following data were collected for a total of 75 races: time in the swimming leg (TSL); position after the swimming leg (PSL); time difference with the first triathlete after the swimming leg (DFT); and final race position. The race levels were divided according to participant levels as follows: world series (WS) (n = 22); World Cup (WC) (n = 22); Continental Cup (CC) (n = 19); national championship (N) (n = 5); and local race (L) (n = 5). Based on distance, they were divided into Olympic distance (OD) (n = 37) and sprint distance (SD) (n = 38). A moderate to strong positive association was found between LT1, LT2, S L200 and PSL and TSl at all race levels except for the SD CC, SD WC, and OD CC races, where no or weak-to-moderate correlations were found. The present study demonstrated that performance measured in a graded multi-stage pool lactate test can predict performance in a triathlon swimming segment. This finding is highly useful for coaches as it can help them to obtain a reliable measure of the triathlete's specific capabilities in the swimming leg.
Knowing which discipline contributes most to a triathlon performance is important to plan race pacing properly. To date, we know that the running split is the most decisive discipline in the Olympic distance triathlon, and the cycling split is the most important discipline in the full-distance Ironman® triathlon. However, we have no knowledge of the Ironman® 70.3. This study intended to determine the most crucial discipline in age group athletes competing from 2004 to 2020 in a total of 787 Ironman® 70.3 races. A total of 823,459 athletes (198,066 women and 625,393 men) from 240 different countries were analyzed and recorded in 5-year age groups, from 18 to 75 + years. Correlation analysis, multiple linear regression, and two-way ANOVA were applied, considering p < 0.05. No differences in the regression analysis between the contributions of the swimming, cycling, and running splits could be found for all age groups. However, the correlation analysis showed stronger associations of the cycling and running split times than the swimming split times with overall race times and a smaller difference in swimming performance between males and females in age groups 50 years and older. For age group triathletes competing in Ironman® 70.3, running and cycling were more predictive than swimming for overall race performance. There was a progressive reduction in the performance gap between men and women aged 50 years and older. This information may aid triathletes and coaches in planning their race tactics in an Ironman® 70.3 race.
Studies comparing the two classes of stimuli (concentric and eccentric) have shown differences in the improvement of cardiovascular, metabolic, and muscle strength gain. This is an experimental, quantitative, and prospective study that aimed to verify the effect of eccentric exercise on glycolytic consumption and kinetics. The blood glucose kinetics of 17 male subjects was evaluated during a treadmill exercise with a 10% declined floor and velocity that required a 60% metabolic activity of VO2max, for 30 minutes. Seventy-two hours later, the same subjects exercised on the treadmill with a 10% inclined floor and 60% VO2max, for 30 minutes. To quantify glucose, blood samples were collected before the exercise, every three minutes along the 30 minutes of physical activity, and five and 10 minutes after finishing the exercise. For the downward slope, there was a homogeneous group behavior for blood glucose dynamics during the exercise, which was characterized by a monotonic decrease of glucose levels until reaching a minimum value at experimental times between 20 and 30 min, followed by a progressive recovery toward initial values. For the acclivity condition, blood glucose dynamics did not follow such a homogeneous behavior. A set of different types of dynamics could be identified. Experimental data showed that the type of dynamics could be predicted, to some extent, by the basal blood glucose level of subjects. The type of floor slope (upward or downward) directly affected glycolytic consumption and kinetics for the individuals analyzed.
Purpose: This study aims to investigate the relationship between split disciplines and overall extreme ultra-triathlon (EUT) performance and verify the relationship among physiological and neuromuscular measurements with both fractional and total EUT performance while checking which variables could predict partial and overall EUT race time. Methods: Eleven volunteers (37 ± 6 years; 176.9 ± 6.1 cm; 77.9 ± 10.9 kg) performed two maximal graded tests (cycling and running) for physiological measurements and muscle strength/power tests to assess neuromuscular functions. Results: The correlation of swimming split times to predict overall EUT race times was lower than for cycling and running split times (r2 = 0.005; p > .05; r2 = 0.949; p < .001 and r2 = 0.925; p < .001, respectively). VO2peak obtained during running test (VO2peakrun) and VT power output assessed during cycling test (VTPO) were the highest predictors of cycling performance (r2 = 0.92; p = .017), whereas VO2peakrun and peakpower output in the cycling test (PPO) were the highest predictors of running performance (r2 = 0.94; p = .008). Conclusion: VO2peakrun and VTPO, associated to jump height assessed during countermovement jump (CMJ) test were the highest correlated variables to predict total EUT performance (r2 = 0.99; p = .007). In practical terms, coaches should include the assessment of VO2peakrun, VTPO, and CMJ to evaluate the athletes’ status and monitor their performance throughout the season. Future studies should test how the improvement of these variables would affect EUT performance during official races.
This study compared central and peripheral fatigue development between the Sprint and Olympic distance triathlon. Fifteen male triathletes performed Sprint and Olympic triathlon simulations in a randomized and counterbalanced order. Central and peripheral fatigue was evaluated from changes in voluntary activation level (VAL) and twitch responses of quadriceps muscle (Qtw,pot), respectively. Qtw,pot reduced from baseline to post-swimming similarly between triathlon simulations (Sprint,−17±11%; Olympic, −13±9%). In post-cycling, Qtw,pot further declined to a similar extent between triathlon distances (Sprint, −31±15%; Olympic, −28±11%). In post-running, Qtw,pot was fully recovered in the Olympic triathlon (−4±10%), whereas there was only a partial recovery of Qtw,pot in the Sprint triathlon (−20±11%). VAL was not reduced in post-swimming, but reduction was similar between triathlon distances in post-cycling (Sprint, −10±9%; Olympic, −8±8%) and post-running (Sprint, −15±14%; Olympic, −16±8%). In the Sprint triathlon, the swimming speed (1.07±0.13m.s⁻¹) was above (p <.001) critical speed (1.01±0.14m.s⁻¹), the cycling power (179.7±27.2W) was below the respiratory compensation point (216.3±27.8W, p <.001) and running speed (13.7±1.05km.h⁻¹) similar to the respiratory compensation point (13.2±0.70km.h⁻¹, p =.124). In the Olympic triathlon, swimming speed (1.03±0.13m.s⁻¹) was similar to critical speed (p =.392), and cycling power (165.3±27.3W) and running speed (12.6±1.05km.h⁻¹) were below the respiratory compensation point (p ≤.007). In conclusion, peripheral fatigue progressed until post-cycling regardless of triathlon distances. However, peripheral fatigue was fully recovered after running in Olympic but not in Sprint triathlon. The central fatigue started in post-cycling and progressed until post-running regardless of triathlon distances.
• Highlights
• The quadriceps muscle peripheral fatigue progresses similarly in Sprint and Olympic triathlons until post-cycling.
• The quadriceps muscle peripheral fatigue is completely recovered after running in the Olympic triathlon, whereas it is partially recovered in the Sprint triathlon.
• The central fatigue starts in post-cycling and progresses similarly until post-running in Sprint and Olympic triathlons, regardless of triathlon distances.
Sex differences in triathlon performance have been decreasing in recent decades and little information is available to explain it. Thirty-nine male and eighteen female amateur triathletes were evaluated for fat mass, lean mass, maximal oxygen uptake (VO2 max), ventilatory threshold (VT), respiratory compensation point (RCP), and performance in a national Olympic triathlon race. Female athletes presented higher fat mass (p = 0.02, d = 0.84, power = 0.78) and lower lean mass (p < 0.01, d = 3.11, power = 0.99). VO2 max (p < 0.01, d = 1.46, power = 0.99), maximal aerobic velocity (MAV) (p < 0.01, d = 2.05, power = 0.99), velocities in VT (p < 0.01, d = 1.26, power = 0.97), and RCP (p < 0.01, d = 1.53, power = 0.99) were significantly worse in the female group. VT (%VO2 max) (p = 0.012, d = 0.73, power = 0.58) and RCP (%VO2 max) (p = 0.005, d = 0.85, power = 0.89) were higher in the female group. Female athletes presented lower VO2 max value, lower lean mass, and higher fat mass. However, females presented higher values of aerobic endurance (%VO2 max), which can attenuate sex differences in triathlon performance. Coaches and athletes should consider that female athletes can maintain a higher percentage of MAV values than males during the running split to prescribe individual training.
State University of Jakarta students, especially the Faculty of Sports Science, consist of athletes in their respective sports, they are required to have various physical abilities or movement skills and master the techniques of these sports, as well as being able to apply them in competitions or sports competitions that they participate in, as well as are required to have achievements in the sport they do. To get an achievement, athletes must have excellent physical fitness and be supported by ideal body proportions and have high enthusiasm and motivation. This study aims to determine the condition of IMT and VO2max male junior athletes in Futsal and soccer sports at State University of Jakarta. This type of research is quantitative research using survey techniques with the method used is descriptive. The results of this study are it can be said that the IMT condition of male junior athletes in futsal and soccer at State University of Jakarta is underweight category as much as 10% or 5 athletes, normal category is 64% or 32 athletes, overweight category is 12% or 6 athletes, and obesity category as much as 14% or 7 athletes. Meanwhile, the results of the calculation of the percentage of VO2max data for male junior athletes in futsal and soccer at State University of Jakarta are 12% or 6 athletes, either 18% or 9 athletes, 44% or 22 athletes, enough categories and the less category was 26% or 13 athletes, while the lacking category was not included in the category.
This brief review investigates how sex influences triathlon performance. Performance time for both Olympic distance and Ironman distance triathlons, and physiological considerations are discussed for both elite and non-elite male and female triathletes. The relative participation of female athletes in triathlon has increased over the last three decades, and currently represents 25–40% of the total field. Overall, the sex difference in both Olympic and Ironman distance triathlon performance has narrowed across the years. Sex difference differed with exercise mode and exercise duration. For non-elite Ironman triathletes, the sex difference in swimming time (≈12%) is lower than that which was evidenced for cycling (≈15%) and running (≈18%). For elite triathletes, sex difference in running performance is greater for Olympic triathlon (≈14%) than it is for Ironman distance triathlon (≈7%). Elite Ironman female triathletes have reduced the gap to their male counterparts to less than 10% for the marathon. The sex difference in triathlon performance is likely to be due to physiological (e.g., VO2max) and morphological (e.g., % body fat) factors but hormonal, psychological and societal (e.g., lower participation rate) differences should also be considered. Future studies should address the limited evidence relating sex difference in physiological characteristics such as lactate threshold, exercise economy or peak fat oxidation.
We aimed to determine which discipline had the greater performance improvement in the history of Ironman triathlon in Hawaii and also which discipline has the greater influence in overall result. Methods: Data from 1983 to 2018 of top 3 women and men of each year that competed in the Ironman World Championship were included. In addition to exploratory data analyses, linear regressions between split time and years of achievement were performed. Further, a stepwise multiple linear regression was applied using total race time as the dependent variable and splits as independent variables. Results: Both women and men significantly improved their performances from 1983 to 2018 in the Ironman World Championship. Swimming had the largest difference in improvements between men and women (3.0 versus 12.1%). A negative and significant decrease in each discipline was identified for both women and men, being cycling the discipline with the greatest reduction. The results from the stepwise multiple regression indicated that cycling was the discipline with more influence in overall time for both sexes. Conclusion: Cycling seems to be the triathlon discipline that most improved race time performances and is also the discipline with greater influence in overall result in the Ironman World Championship in elite men and women.
A common null polymorphism in the ACTN3 gene (rs1815739:C>T) results in replacement of an arginine (R) with a premature stop codon (X) at amino acid 577 in the fast muscle protein α‐actinin‐3. The ACTN3 p.Arg577Ter allele (aka p.R577* or R577X) has undergone positive selection, with an increase in the X allele frequency as modern humans migrated out of Africa into the colder, less species‐rich Eurasian climates suggesting that the absence of α‐actinin‐3 may be beneficial in these conditions. Approximately 1.5 billion people worldwide are completely deficient in α‐actinin‐3. While the absence of α‐actinin‐3 influences skeletal muscle function and metabolism this does not result in overt muscle disease. α‐Actinin‐3 deficiency (ACTN3 XX genotype) is constantly underrepresented in sprint/power performance athletes. However, recent findings from our group and others suggest that the ACTN3 R577X genotype plays a role beyond athletic performance with effects observed in ageing, bone health and inherited muscle disorders such as McArdle disease and Duchenne muscle dystrophy. In this review, we provide an update on the current knowledge regarding the influence of ACTN3 R577X on skeletal muscle function and its potential biological and clinical implications. We also outline future research directions to explore the role of α‐actinin‐3 in healthy and diseased populations.
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There are strong genetic components to cardiorespiratory fitness and its response to exercise training. It would be useful to understand the differences in the genomic profile of highly trained endurance athletes of world class caliber and sedentary controls. An international consortium (GAMES) was established in order to compare elite endurance athletes and ethnicity-matched controls in a case-control study design. Genome-wide association studies were undertaken on two cohorts of elite endurance athletes and controls (GENATHLETE and Japanese endurance runners), from which a panel of 45 promising markers was identified. These markers were tested for replication in seven additional cohorts of endurance athletes and controls: from Australia, Ethiopia, Japan, Kenya, Poland, Russia and Spain. The study is based on a total of 1520 endurance athletes (835 who took part in endurance events in World Championships and/or Olympic Games) and 2760 controls. We hypothesized that world-class athletes are likely to be characterized by an even higher concentration of endurance performance alleles and we performed separate analyses on this subsample. The meta-analysis of all available studies revealed one statistically significant marker (rs558129 at GALNTL6 locus, p = 0.0002), even after correcting for multiple testing. As shown by the low heterogeneity index (I2 = 0), all eight cohorts showed the same direction of association with rs558129, even though p-values varied across the individual studies. In summary, this study did not identify a panel of genomic variants common to these elite endurance athlete groups. Since GAMES was underpowered to identify alleles with small effect sizes, some of the suggestive leads identified should be explored in expanded comparisons of world-class endurance athletes and sedentary controls and in tightly controlled exercise training studies. Such studies have the potential to illuminate the biology not only of world class endurance performance but also of compromised cardiac functions and cardiometabolic diseases.
Recently, a high prevalence of morning-types was reported among trained South African endurance athletes. Proposed explanations for this observation were that either the chronotype of these athletes is better suited to coping with the early-morning start times of endurance events in South Africa; or habitual early waking for training or endurance events may have conditioned the athletes to adapt and become morning-types. The South African endurance athletes also had earlier chronotypes compared to a control population of less active individuals, suggesting that individuals who are more physically active may have earlier chronotypes. However, since both the South African athlete and control groups showed an overrepresentation of morning-types compared to European and American populations, the South African climate may in part have explained this bias towards morningness. Given the latitude and climate differences between South Africa and the Netherlands, and that South African marathons typically start at about 06:30 while those in the Netherlands start later (±11:00), comparison of South African and Dutch marathon runners and active controls would allow for simultaneous assessment of the effects of marathon start time, degree of physical activity and climate on chronotype. Therefore, the primary aims of this study were: (i) to assess the effect of marathon start time on chronotype in marathon runners and (ii) to determine the extent to which either degree of physical activity or climate might explain the bias towards morningness observed in South African athletes and controls. A secondary aim was to determine whether any relationships exist between chronotype, PERIOD3 (PER3) variable number tandem repeat (VNTR) polymorphism genotype, habitual training habits and marathon performance. Trained male marathon runners from South Africa (n = 95) and the Netherlands (n = 90), and active but non-competitive male controls from South Africa (n = 97) and the Netherlands (n = 98) completed a questionnaire capturing demographics, training and race history, as well as the Horne-Östberg morningness-eveningness personality questionnaire. All participants donated buccal cell samples from which genomic DNA was extracted and polymerase chain reaction analysis was used to genotype them for the PER3 VNTR polymorphism, which has previously been associated with chronotype. The main finding was that South African runners were significantly more morning-orientated than Dutch runners suggesting that participation in an endurance sport with an earlier start time may influence chronotype. Secondly, both the South African and Dutch runners were significantly more morning-orientated than their respective control groups, indicating that individuals who train for and participate in recreational endurance sport races have an earlier chronotype than physically active but non-competitive males. Thirdly, mean chronotype scores were similar between the South African and Dutch control groups, suggesting that climate does not seem to affect chronotype in these groups. Fourthly, the PER3 VNTR polymorphism distribution was similar between the four groups and was not associated with chronotype, suggesting that the difference in chronotype between the four groups in this study is not explained by the PER3 VNTR genotype. Lastly, in the South African runners group, a higher preference for mornings was associated with a better personal best half-marathon and current marathon performance.
The present study aimed to describe heart rate (HR) responses during a simulated Olympic boxing match and examine physiological parameters of boxing athletes. Ten highly trained Olympic boxing athletes (six men and four women) performed a maximal graded exercise test on a motorized treadmill to determine maximal oxygen uptake (52.2 mL · kg(-1) · min(-1) ± 7.2 mL · kg(-1) · min(-1)) and ventilatory thresholds 1 and 2. Ventilatory thresholds 1 and 2 were used to classify the intensity of exercise based on respective HR during a boxing match. In addition, oxygen uptake (V̇O2) was estimated during the match based on the HR response and the HR-V̇O2 relationship obtained from a maximal graded exercise test for each participant. On a separate day, participants performed a boxing match lasting three rounds, 2 minutes each, with a 1-minute recovery period between each round, during which HR was measured. In this context, HR and V̇O2 were above ventilatory threshold 2 during 219.8 seconds ± 67.4 seconds. There was an increase in HR and V̇O2 as a function of round (round 3 < round 2 < round 1, P < 0.0001). These findings may direct individual training programs for boxing practitioners and other athletes.
Background: Previous studies concerning the relevance of the BDKRB2 gene polymorphisms revealed that the absence (–9 allele) of a 9 base pair sequence in exon 1 of the BDKRB2 gene is correlated with higher skeletal muscle metabolic efficiency, glucose uptake during exercise, as well as endurance athletic performance. Aim: The aim of the study was to investigate the association between the BDKRB2 -9/+9 polymorphism and elite athletic status in two cohorts of east-European athletes. Therefore, we examined the genotype distribution of the BDKRB2 9/+9 polymorphic site in a group of Polish athletes and confirmed the results obtained in a replication study of Russian athletes.. Methods: Three hundred and two Polish athletes and 684 unrelated sedentary controls as well as 822 Russian athletes and 507 unrelated sedentary volunteers were recruited for this study. All samples were genotyped for the -9/+9 polymorphism within exon 1 of the BDKRB2 gene using a polymerase chain reaction (PCR). Significance was assessed by χ2 analysis with Bonferroni’s correction for multiple testing. Results: We have not found any statistical difference in the -9/+9 genotype and allele frequencies in two groups of athletes divided into four subgroups, i.e. endurance, sprintendurance, sprint-strength and strength athletes, when compared with controls. There weren’t any significant differences found in allele frequencies (P = 0.477) and genotype distribution (P = 0.278) in the initial and replication studies. Conclusion: No association was found between the BDKRB2 -9/+9 polymorphism and elite athletic status in two cohorts of east- European athletes
OBJETIVO: Investigar a tipologia circadiana e as diferenças de gênero em universitários do sul do Brasil. MÉTODOS: Voluntários (736) de 17 a 49 anos preencheram a versão brasileira do Questionário de Cronotipo (QC), tradução do Morningnesseveningness Questionnaire (MEQ) de Horne e Östberg. Medidas de tendência central e dispersão e curva de distribuição dos escores do QC (Kolmogorov-Smirnov) foram calculadas de acordo com gênero (teste t de Student), idade, estação de nascimento e desconforto com o horário de verão (qui-quadrado). RESULTADOS: Foram incluídos 648 indivíduos (36% homens, 64% mulheres), com perdas de 12% por questionários incorretos. A distribuição dos escores do QC evidenciou uma curva normal (amplitude = 18-77; média = 46,6; desvio-padrão = 10,8). Nesta amostra, 32% foram vespertinos, 54% intermediários e 14% matutinos. As médias do QC foram significativamente diferentes (p = 0,003): homens (44,9 ± 10,8) comparados com mulheres (47,5 ± 10,7) e 70% dos que nasceram na primavera e no verão foram vespertinos (p = 0,015), sem associação gêneroestação do ano. CONCLUSÃO: Homens e nascidos na primavera-verão evidenciaram preferência pela vespertinidade, não havendo diferença de gênero com relação à estação de nascimento. Nossos resultados estão de acordo com estudos realizados no hemisfério norte que mostraram, também, uma associação entre a estação de nascimento e o cronotipo.
Genetic polymorphism is suggested to be associated with human physical performance. The angiotensin I-converting enzyme insertion/deletion (ACE I/D) polymorphism and the α-actinin-3 gene (ACTN3) R577X polymorphism have been most widely studied for such association analysis. However, the findings are frequently heterogeneous. We aim to summarize the associations of ACE I/D and ACTN3 R577X with sport performance by means of meta-analysis.
We systematically reviewed and quantitatively summarized published studies, until October 31, 2012, on relationship between ACE/ACTN3 genetic polymorphisms and sports performance, respectively.
A total of 366 articles on ACE and 88 articles on ACTN3 were achieved by literature search. A significant association was found for ACE II genotype compared to D allele carriage (DD+ID) with increased possibility of physical performance (OR, 1.23; 95% CI, 1.05-1.45). With respect to sport discipline, the II genotype was found to be associated with performance in endurance athletes (OR, 1.35; 95% CI, 1.17-1.55). On the other hand, no significant association was observed for ACTN3 RR genotype as compared to X allele carriage (XX+RX) (OR, 1.03; 95% CI, 0.92-1.15). However, when restricted the analyses to power events, a significant association was observed (OR, 1.21; 95% CI, 1.03-1.42).
Our results provide more solid evidence for the associations between ACE II genotype and endurance events and between ACTN3 R allele and power events. The findings suggest that the genetic profiles might influence human physical performance.
Angiotensin I-converting enzyme (ACE) is recognized as one of the main effector molecules involved in blood pressure regulation. In the last few years some polymorphisms of ACE such as the insertion/deletion (I/D) polymorphism have been described, but their physiologic relevance is poorly understood. In addition, few studies investigated if the specific activity of ACE domain is related to the I/D polymorphism and if it can affect other systems. The aim of this study was to establish a biochemical and functional characterization of the I/D polymorphism and correlate this with the corresponding ACE activity. For this purpose, 119 male brazilian army recruits were genotyped and their ACE plasma activities evaluated from the C- and N-terminal catalytic domains using fluorescence resonance energy transfer (FRET) peptides, specific for the C-domain (Abz-LFK(Dnp)OH), N-domain (Abz-SDK(Dnp)P-OH) and both C- and N-domains (Abz-FRK(Dnp)P-OH). Plasma kallikrein activity was measured using Z-Phe-Arg-AMC as substrate and inhibited by selective plasma kallikrein inhibitor (PKSI). Some physiological parameters previously described related to the I/D polymorphism such as handgrip strength, blood pressure, heart rate and BMI were also evaluated. The genotype distribution was II n=27, ID n=64 and DD n=28. Total plasma ACE activity of both domains in II individuals was significantly lower in comparison to ID and DD. This pattern was also observed for C- and N-domain activities. Difference between ID and DD subjects was observed only with the N-domain specific substrate. Blood pressure, heart rate, handgrip strength and BMI were similar among the genotypes. This polymorphism also affected the plasma kallikrein activity and DD group presents high activity level. Thus, our data demonstrate that the I/D ACE polymorphism affects differently both ACE domains without effects on handgrip strength. Moreover, this polymorphism influences the kallikrein-kinin system of normotensive individuals.
Whether the Met235Thr (rs699) variation in the angiotensinogen (AGT) gene, encoding a threonine instead of a methionine in codon 235 of the mature protein, is associated with athletic performance remains to be elucidated. We compared the genotype and allele frequencies for the AGT Met235Thr variation (rs699) in 119 nonathletic controls, 100 world-class endurance athletes (professional cyclists, Olympic-class runners), and 63 power athletes (top-level jumpers, throwers, sprinters). Participants were all males and from the same descent (Caucasian) for > or =3 generations. The proportion of the CC genotype was significantly higher in the power group (34.9%) than in either the control (16%) or the endurance group (16%) (p = 0.008 and p = 0.005, respectively). The odds ratio (95% CI) of being a power athlete if the subject has a CC genotype was 1.681 (1.176-2.401), compared with the control group. In summary, the C allele of the AGT Met235Thr polymorphism might favour power sports performance. Although more research is needed, this could be attributed to the higher activity of angiotensin II, a skeletal muscle growth factor.
The aim of the present study was to determine the best pacing strategy to adopt during the initial phase of a short distance triathlon run for highly trained triathletes. Ten highly trained male triathletes completed an incremental running test to determine maximal oxygen uptake, a 10-km control run at free pace and three individual time-trial triathlons (1.5-km swimming, 40-km cycling, 10-km running) in a randomised order. Swimming and cycling speeds were imposed as identical to the first triathlon performed and the first run kilometre was done alternatively 5% faster (Tri-Run(+5%)), 5% slower (Tri-Run(-5%)) and 10% slower (Tri-Run(-10%)) than the control run (C-Run). The subjects were instructed to finish the 9 remaining kilometres as quickly as possible at a free self-pace. Tri-Run(-5%) resulted in a significantly faster overall 10-km performance than Tri-Run(+5%) and Tri-Run(-10%) (p < 0.05) but no significant difference was observed with C-Run (p > 0.05) (2,028 +/- 78 s vs. 2,000 +/- 72 s, 2,178 +/- 121 s and 2,087 +/- 88 s, for Tri-Run(-5%), C-Run, Tri-Run(+5%) and Tri-Run(-10%), respectively). Tri-Run(+5%) strategy elicited higher values for oxygen uptake, ventilation, heart rate and blood lactate at the end of the first kilometre than the three other conditions. After 5 and 9.5 km, these values were higher for Tri-Run(-5%) (p < 0.05). The present results showed that the running speed achieved during the cycle-to-run transition is crucial for the improvement of the running phase as a whole. Triathletes would benefit to automate a pace 5% slower than their 10-km control running speed as both 5% faster and 10% slower running speeds over the first kilometre involved weaker overall performances.
An English language self-assessment Morningness-Eveningness questionnaire is presented and evaluated against individual differences in the circadian vatiation of oral temperature. 48 subjects falling into Morning, Evening and Intermediate type categories regularly took their temperature. Circadian peak time were identified from the smoothed temperature curves of each subject. Results showed that Morning types and a significantly earlier peak time than Evening types and tended to have a higher daytime temperature and lower post peak temperature. The Intermediate type had temperatures between those of the other groups. Although no significant differences in sleep lengths were found between the three types, Morning types retired and arose significantly earlier than Evening types. Whilst these time significatly correlated with peak time, the questionnaire showed a higher peak time correlation. Although sleep habits are an important déterminant of peak time there are other contibutory factors, and these appear to be partly covered by the questionnaire. Although the questionnaire appears to be valid, further evaluation using a wider subject population is required.
The purpose of this investigation was to study the relationship between perceptual ratings from Borg's new category-ratio scale and some physiological variables during exercise. To accomplish this, scale ratings were related to blood and muscle lactate accumulation and heart rates during a progressive, maximal exercise test on the cycle ergometer. Ten physically active males were utilized as subjects; lactate data were recorded on only 7 of the 10 subjects. Three ratings of perceived exertion were made at each stage of the exercise test: leg effort (LE), cardiorespiratory effort (CE), and leg pain (LP). All ratings showed a positively accelerating increase with exercise intensity as did both blood and muscle lactate, while heart rate increased linearly. The exponents of the power functions describing the perceptual variation ranged from 1.63-1.67 compared to 2.2 for blood lactate and 2.7 for muscle lactate. Polynomial analysis revealed a similar quadratic trend for both perceptual and blood lactate data; however, muscle lactate demonstrated a cubic trend. No significant differences were found between CE and LE at 100, 200, and 300 W (P greater than 0.05). Subjects with the highest percentage of slow-twitch muscle fibers (mean ST%=51.14) rated LE and CE significantly lower ( mean of all power outputs, 0-300 W) than those with the lowest ST% (mean=34.52). It is concluded that the ratings from the category-ratio scale correspond very well with glycogenolytic metabolism leading to lactate accumulation during exercise.
When running indoors on a treadmill, the lack of air resistance results in a lower energy cost compared with running outdoors at the same velocity. A slight incline of the treadmill gradient can be used to increase the energy cost in compensation. The aim of this study was to determine the treadmill gradient that most accurately reflects the energy cost of outdoor running. Nine trained male runners, thoroughly habituated to treadmill running, ran for 6 min at six different velocities (2.92, 3.33, 3.75, 4.17, 4.58 and 5.0 m s-1) with 6 min recovery between runs. This routine was repeated six times, five times on a treadmill set at different grades (0%, 0%, 1%, 2%, 3%) and once outdoors along a level road. Duplicate collections of expired air were taken during the final 2 min of each run to determine oxygen consumption. The repeatability of the methodology was confirmed by high correlations (r = 0.99) and non-significant differences between the duplicate expired air collections and between the repeated runs at 0% grade. The relationship between oxygen uptake (VO2) and velocity for each grade was highly linear (r > 0.99). At the two lowest velocities, VO2 during road running was not significantly different from treadmill running at 0% or 1% grade, but was significantly less than 2% and 3% grade. For 3.75 m s-1, the VO2 during road running was significantly different from treadmill running at 0%, 2% and 3% grades but not from 1% grade. For 4.17 and 4.58 m s-1, the VO2 during road running was not significantly different from that at 1% or 2% grade but was significantly greater than 0% grade and significantly less than 3% grade. At 5.0 m s-1, the VO2 for road running fell between the VO2 value for 1% and 2% grade treadmill running but was not significantly different from any of the treadmill grade conditions. This study demonstrates equality of the energetic cost of treadmill and outdoor running with the use of a 1% treadmill grade over a duration of approximately 5 min and at velocities between 2.92 and 5.0 m s-1.
Performance is related to body morphology in many sports. With triathlon making its debut into the Olympic programme in 2000, it was deemed important to determine which physical characteristics of elite-level triathletes were significantly related to performance. Seventy-one elite and junior elite triathletes, from 11 nations, competing at the 1997 World Triathlon Championships were measured on a battery of 28 anthropometric dimensions. A factor analysis was conducted, which reduced the number of variables to four and these were used in a stepwise linear regression to determine which morphological factors were important to performance. Elite triathletes were significantly (p < 0.05) faster than their junior counterparts (males 1:52:26 vs. 2:03:23 and females 2:07:01 vs. 2:14:05) and showed less variation in performance times. Run time variation was the largest of the component disciplines and tended to show the importance of this discipline to the final outcome. Following a factor analysis the four distinguishable morphological factors that emerged were: robustness, adiposity, segmental lengths and skeletal mass. Relating these factors to the total time obtained by the triathletes in this study yielded a regression equation that correlated significantly with all triathletes, accounting for 47% of the variance in total triathlon duration. The regression equations illustrated the importance of low levels of adiposity for elite triathletes for total time and most of the subdisciplines. The other factor that showed importance was that proportionally longer segmental lengths contributed to successful swimming outcome.
Maximal heart rate (HRmax)-prediction equations based on a person's age are frequently used in prescribing exercise intensity and other clinical applications. Results from various cross-sectional studies have shown a linear decrease in HRmax during exercise with increasing age. However, it is less well established that longitudinal tracking of the same individuals' HRmax as they age exhibits an identical linear relationship. This study examined the longitudinal relationship between age and HRmax during exercise.
A retrospective analysis of maximal graded exercise test (GXT) results for members participating in a university-based health-assessment/fitness center between 1978 and 2003 was undertaken in 2006. Records were examined from individuals (N = 132) of both sexes who represented a broad range of age and fitness levels and who had multiple GXT (total N = 908) conducted over 25 years. HRmax-prediction equations based on participants' age and HRmax elicited during the tests were developed using a linear mixed-models statistical analysis approach.
Clinical measurements obtained during the administration of the GXT included in this longitudinal study resulted in the generation of a univariate prediction model: HRmax = 207 - 0.7 x age. Model parameters were highly statistically significant (P < 0.001).
The relationship between age and HRmax during exercise developed in this longitudinal study has resulted in a prediction equation appreciably different from the conventional HRmax formula (220 - age) often used in exercise prescription, and it confirms findings from recent cross-sectional investigations of HRmax.
Performance in triathlon is dependent upon factors that include somatotype, physiological capacity, technical proficiency and race strategy. Given the multidisciplinary nature of triathlon and the interaction between each of the three race components, the identification of target split times that can be used to inform the design of training plans and race pacing strategies is a complex task. The present study uses machine learning techniques to analyse a large database of performances in Olympic distance triathlons (2008-2012). The analysis reveals patterns of performance in five components of triathlon (three race "legs" and two transitions) and the complex relationships between performance in each component and overall performance in a race. The results provide three perspectives on the relationship between performance in each component of triathlon and the final placing in a race. These perspectives allow the identification of target split times that are required to achieve a certain final place in a race and the opportunity to make evidence-based decisions about race tactics in order to optimise performance.
Recently, a fully automated method for segmenting abdominal fat into subcutaneous fat and visceral fat (VF) within the android region using dual-energy X-ray absorptiometry (DXA) has been newly developed. The purpose of this study was to validate a new DXA method by comparing it to the gold standard, computed tomography (CT), in the Korean population. Furthermore, we examined its reliability regarding VF and explored whether it is applicable to the Asian population, which has relatively larger amount of VF. We studied 123 adult men and women, aged 22-73 yr, representing a wide range of body mass index values (17.1-36.0 kg/m(2)), who underwent both DXA and CT in a fasting state within 1 h. The coefficient of determination (r(2)) for regression of the CT on DXA values was 0.892 for females, 0.838 for males, and 0.931 combined. Bland-Altman bias was -451.4 cm(3) with 95% limits of agreement of 149.8 to -1052.6 cm(3). The DXA-measured VF showed a better correlation with CT-measured VF volume than common indices for adiposity, including the body mass index and waist circumference. There was a lesser discrepancy ratio between DXA- and CT-measured VF with an increase of VF volume. DXA, a relatively convenient, inexpensive, and safe method with minimum radiation dosage, can be a reliable technique for VF assessment in the Asian population.
Copyright © 2015 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.
Oxygen cost (OC) is commonly employed to assess an athlete's running economy, though the validity of this measure is often overlooked.
This study evaluated the validity of OC as a measure of running economy by comparison to the underlying energy cost (EC). Additionally, the most appropriate method of removing the influence of body mass was determined to elucidate a measure of running economy that enables valid inter-individual comparisons.
172 highly trained endurance runners (males, n = 101; females, n = 71) performed a discontinuous submaximal running assessment, consisting of approximately seven 3 min stages (1 km [BULLET OPERATOR] hr increments), to determine the absolute OC (L [BULLET OPERATOR] km) and EC (Kcal [BULLET OPERATOR] km) for the 4 speeds below lactate turnpoint.
Comparisons between models revealed linear ratio scaling to be a more suitable method than power function scaling for removing the influence of body mass for both EC (R; males, 0.589 vs 0.588; females, 0.498 vs 0.482) and OC (males, 0.657 vs 0.652; females, 0.532 vs 0.531). There were stepwise increases in EC and RER with increments in running speed (both, P < 0.001). However, no differences were observed for OC across the 4 monitored speeds (P = 0.54).
Whilst EC increased with running speed, OC was insensitive to changes in running speed, and therefore does not appear to provide a valid index of the underlying EC of running, likely due to the inability of OC to account for variations in substrate utilisation. Therefore, EC should be employed as the primary measure of running economy, and for runners an appropriate scaling with body mass is recommended.
The swim section of Sprint- and Olympic-distance triathlon race formats is integral to the success of subsequent cycle and running disciplines, and to overall race performance. The current body of swimming-based triathlon research suggests that the energy used, and the positioning gained among competitors during the swim, is important in determining the success of an athlete's race, especially professional athletes in draft-legal settings. Furthermore, by swimming at a reduced intensity, it has been shown that the performance of the subsequent disciplines may be enhanced. However, reductions in energy output can be obtained without compromising swimming speed. This review highlights the importance of swimming intensity during a triathlon and how it impacts on the ensuing cycle and run. Furthermore, consideration is given to current methods used to manipulate swimming performance.
Previous research (study 1) has shown that a significant relationship exists between 10 km run time (RT) and predicted running velocity at VO2max (vVO2max) among well-trained males heterogeneous in VO2max. Since competitive runners often display a homogeneous fitness profile, the purpose of this study was to determine the association between 10 km RT and vVO2max among a group of trained runners exhibiting nearly identical VO2max values (study 2). Running economy (RE), vVO2max, and velocity at a 4 mM blood lactate concentration (v at 4 mM BL) were calculated in both studies. Correlations were obtained as shown in Table 2. The relationship between VO2max and 10 km RT achieved statistical significance only in study 1, while RE explained a greater amount of performance variation in study 2. In both studies, variation in 10 km RT attributable to vVO2max was similar and exceeded that due to either VO2max or RE. vVO2max also accounted for essentially the same amount of variation in 10 km RT as did v at 4 mM BL. It was concluded that, among well-trained subjects homogeneous in VO2max, a strong relationship exists between 10 km RT and vVO2max that appears to be mediated to a large extent by RE.
The present study was carried out in order to quantify the athlete's endurance impairment after two out of three sequential events of Olympic Triathlon (OT). Furthermore the significance of ventilatory threshold (Tvent) and peak of oxygen uptake (VO2peak) as triathlete's performance predictors was assessed. Tvent and VO2peak were measured in six male triathletes performing an incremental treadmill test a week before an ad hoc triathlon event. The same test was applied immediately after the first two segments of the triathlon (1.5 km swim, 32 km bike). VO2peak and Tvent measured during the latter test were reduced compared to the first test. VO2peak decreased from 69 to 64 ml.kg-1.min-1 and Tvent from 58 to 51 ml.kg-1.min-1 p < 0.01), respectively. VO2peak and Tvent measured in the first test were well correlated (P < 0.05) to both running and cycling times. The Tvent measured during the second test was related to the running time but with a higher significance (p < 0.01) than in the first test. The impairment in the endurance performance induced by the first two segments of OT is an important aspect to consider both in training and in race strategy. These results also provide evidence that VO2peak and Tvent are good predictors of triathlon performance at least in cycling and running events.
Most studies of the triathlon have looked at male triathletes with respect to the longer distance events such as the Hawaii Ironman Triathlon. The purpose of this study was to investigate and compare the physiological characteristics and training protocols of elite and competitive (club) women triathletes who compete at Olympic distance (1.5 km swim, 40 km cycle, 10 km run) to examine the relationship between these factors and running performance in the triathlon. The elite triathletes (n = 10) had a lower body mass and BMI than club level triathletes (n = 9) as well as smaller girths at all measured sites although these differences were not significant. Sum of skinfold thickness measured at four sites was significantly smaller in the elite group (p = 0.05), yet, wide individual variations were found within each group. The amount of training undertaken by individuals in both groups varied markedly; however, overall the elite did more training in all disciplines. The VO2max measured on the treadmill was significantly higher (p = 0.03) in the elite women (65.6 +/- 6.0 ml.kg-1.min-1) as compared to the club level women (60.4 +/- 3.1 ml.kg-1.min-1). The elite triathletes were significantly more economical, showing a lowered relative oxygen consumption (% VO2max), (p = 0.008); lowered heart rate (p = 0.01) and lowered blood lactate values (p = 0.03) at 15 km.h-1. The elite group were also much more efficient runners at 15 km.h-1 when looking at VE/VO2 (p = 0.05). An association was found between run race time and %VO2max at 15 km.h-1 (p = 0.04). The results suggest that there is no ideal nor unique anthropometric profile that can be established for female triathletes especially with respect to running time and overall performance. The widespread differences in physiological variables found between the two groups confirms the important contribution factors such as these make to performance.
The purpose of this study was to investigate if selected physiological variables were related to triathlon performance. Eighteen male and seven female triathletes competed in a short-course triathlon (1-km swim, 30-km cycle, 9-km run) and underwent physiological testing within 14 d. VO2max and ventilatory threshold (VT) were measured on a cycle ergometer, treadmill, and tethered swim apparatus. Leg flexion and extension strength were measured on a Cybex II isokinetic dynamometer. Multiple linear regression did not improve the prediction of triathlon performance over that provided by simple correlations. Swim performance was related to relative swim VO2max in both males (r = -0.48) and females (r = -0.93) as well as the resistance pulled at swim VT (r = -0.81) and absolute leg flexion strength (r = -0.77) in females. No physiological variables were significantly related to cycling time in either gender. Running time was related to relative VO2max (r = -0.88) in females and velocity at run VT in both females (r = -0.88) and males (r = -0.73). Relative swim VO2max (r = -0.98), velocity at run VT (r = -0.89), and absolute leg flexion strength (r = -0.80) were related to overall performance in female triathletes. The only significant predictor of overall triathlon time for males was velocity at run VT (r = -0.78). It therefore appears that in short-course triathletes physiological variables in swimming and running are important to overall performance. Differences in sample size, group variability, and level of performance between males and females may account for the reported differences in the physiological predictors of performance between genders.
The physiological demands of sequential exercise in swimming, cycling and running are unique and require the triathlete to develop physical and physiological characteristics that are a blend of those seen in endurance swimming, cycling and running specialists. Elite triathletes are generally tall, of average to light weight and have low levels of body fat, a physique which provides the advantages of large leverage and an optimal power to surface area or weight ratio.
Triathletes have high maximum oxygen uptake (V̇O2max) values, but V̇O2max may be on average marginally lower than values previously observed in endurance specialists. Although V̇O2max is a predictor of performance in triathletes of mixed abilities, it cannot be used to predict performance within homogenous groups of elite performers. Nevertheless, elite triathletes have significantly higher V̇O2max values than sub-elite triathletes and high V̇O2max levels are required for success in triathlons. The ability of the triathlete to exercise at a lower percentage of V̇O2max for a given submaximal workload may be especially important to triathlon success. This is influenced not only by V̇O2max itself, but also by anaerobic threshold and economy of movement.
Anaerobic threshold, as indicated by either ventilatory threshold or lactate threshold, improves with triathlon training and when measured in the appropriate exercise mode has been related to swim, cycle and run performance in the triathlon. Economy of movement in swimming, cycling and running is also related to triathlon performance, and swimming economy in particular appears to be an area where triathletes could make large improvements.
Future research should utilise experimental methodologies to investigate triathlon physiology, in particular, the influence of sequential exercise in different exercise modes on physiological function and examine the influence of different training interventions on triathlon physiology and performance.
In the exercising human, maximal oxygen uptake (VO2max) is limited by the ability of the cardiorespiratory system to deliver oxygen to the exercising muscles. This is shown by three major lines of evidence: 1) when oxygen delivery is altered (by blood doping, hypoxia, or beta-blockade), VO2max changes accordingly; 2) the increase in VO2max with training results primarily from an increase in maximal cardiac output (not an increase in the a-v O2 difference); and 3) when a small muscle mass is overperfused during exercise, it has an extremely high capacity for consuming oxygen. Thus, O2 delivery, not skeletal muscle O2 extraction, is viewed as the primary limiting factor for VO2max in exercising humans. Metabolic adaptations in skeletal muscle are, however, critical for improving submaximal endurance performance. Endurance training causes an increase in mitochondrial enzyme activities, which improves performance by enhancing fat oxidation and decreasing lactic acid accumulation at a given VO2. VO2max is an important variable that sets the upper limit for endurance performance (an athlete cannot operate above 100% VO2max, for extended periods). Running economy and fractional utilization of VO2max also affect endurance performance. The speed at lactate threshold (LT) integrates all three of these variables and is the best physiological predictor of distance running performance.
Four days after competing in an Olympic-distance National Triathlon Championship (1500-m swim, 40-km cycle, 10-km run), five male and five female triathletes underwent comprehensive physiological testing in an attempt to determine which physiological variables accurately predict triathlon race time.
All triathletes underwent maximal swimming tests over 25 and 400 m, the determination of peak sustained power output (PPO) and peak oxygen uptake (VO2peak) during an incremental cycle test to exhaustion, and a maximal treadmill running test to assess peak running velocity and VO2peak. In addition, submaximal steady-state measures of oxygen uptake (VO2), blood [lactate], and heart rate (HR) were determined during the cycling and running tests.
The five most significant (P < 0.01) predictors of triathlon performance were blood lactate measured during steady-state cycling at a workload of 4 W x kg(-1) body mass (BM) (r = 0.92), blood lactate while running at 15 km x h(-1) (r = 0.89), PPO (r = 0.86), peak treadmill running velocity (r = 0.85), and VO2peak during cycling (r = 0.85). Stepwise multiple regression analysis revealed a highly significant (r = 0.90, P < 0.001) relationship between predicted race time (from laboratory measures) and actual race time, from the following calculation: race time (s) = - 129 (peak treadmill velocity [km x h(-1)]) + 122 ([lactate] at 4 W x kg(-1) BM) + 9456.
The results of this study show that race time for top triathletes competing over the Olympic distance can be accurately predicted from the results of maximal and submaximal laboratory measures.
We have previously shown that the insertion allele of the angiotensin-converting enzyme (ACE) gene was over-represented in the fastest South-African-born finishers of the South African Ironman Triathlons. As ACE is a component of the skeletal muscle kallikrein-kinin system (KKS), the aim of this study is to determine if there are any further associations between polymorphisms within the BDKRB2 and NOS3 genes, which encode for the KKS components, bradykinin beta(2) receptor and nitric oxide synthase, respectively, and ultra-endurance performance during the Ironman Triathlons. Four-hundred and forty-three male Caucasian triathletes who completed the 2000 and/or 2001 South African Ironman Triathlons and 203 healthy Caucasian male control subjects were genotyped for the functional -9/+9 polymorphism within exon 1 of the BDKRB2 gene and the G894T NOS3 gene polymorphisms. The BDKRB2 -9/-9 genotype occurred at a significantly higher frequency when the triathlete group (27.0%) was compared with the control group (19.3%, P=0.035). When divided into tertiles, there was also a significant linear trend for the NOS3 GG genotype distribution among the fastest (35.0%), middle (40.4%) and slowest (46.9%) finishers (P=0.039). The overall finishing times of the triathletes with an NOS3 GG genotype together with a BDKRB2 +9 allele were significantly slower than those with other genotype combinations (P=0.001). The NOS3/BDKRB2 genotype (beta=-0.150, B=-31.48, P=0.002), together with body mass index and age, accounted for 14.6% of the variance in the overall race time for the triathlon. In conclusion, both the NOS3 and BDKRB2 genes are associated with the actual performance during the Ironman Triathlons.
Heart rate response during a simulated Olympic boxing match is predominantly above ventilatory threshold 2: a cross sectional study
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Sports Med. 2013:175. https://doi.org/10.2147/oajsm.s44807.
ACSM's Guidelines for Exercise Testing and Prescription
American College of Sports Medicine, ACSM's Guidelines for Exercise Testing and
Prescription, Lippincott Williams & Wilkins, 2013.