Ironman Athletes Research Articles

Beneficial Physiological and Metabolic Effects with Acute Intake of New Zealand Blackcurrant Extract during 4 h of Indoor Cycling in a Male Ironman Athlete: A Case Study.

New Zealand blackcurrant (NZBC) is known to alter exercise-induced physiological and metabolic responses with chronic (i.e., 7 days) dosing. We examined the effects of acute intake of New Zealand blackcurrant (NZBC) extract on 4 h indoor cycling-induced physiological and metabolic responses in a male amateur Ironman athlete (age: 49 years; BMI: 24.3 kg·m-2; V˙O2max: 58.6 mL·kg-1·min-1; maximal aerobic power: 400 W; history: 14 Ironman events in 16 years) three weeks before competition. Indirect calorimetry was used and heart rate was recorded at 30 min intervals during 4 h indoor (~22.4 °C, relative humidity: ~55%) constant power (165 W) cycling on a Trek Bontrager connected to a Kickr smart trainer. Blood lactate and rating of perceived exertion (RPE) were taken at 60 min intervals. Study was a single-blind placebo-controlled study with capsules (4 × 105 mg anthocyanins) taken 2 h before starting the 4 h of cycling. Water was allowed ad libitum with personalised consumption of gels [a total of eight with three with caffeine (100 mg)], two bananas and 8 × electrolyte capsules (each 250 mg sodium and 125 mg potassium) at personalised time-points. With NZBC extract (CurraNZ), during 4 h of cycling (mean of 8 measurements), minute ventilation was 8% lower than placebo. In addition, there was no difference for oxygen uptake, with carbon dioxide production found to be 4% lower with NZBC extract. With the NZBC extract, the ventilatory equivalents were lower for oxygen and carbon dioxide by 5.5% and 3.7%; heart rate was lower by 10 beats·min-1; lactate was 40% different with lower lactate at 2, 3 and 4 h; RPE was lower at 2, 3 and 4 h; and carbohydrate oxidation was 11% lower. With NZBC extract, there was a trend for fat oxidation to be higher by 13% (p = 0.096), with the respiratory exchange ratio being lower by 0.02 units. Acute intake of New Zealand blackcurrant extract (420 mg anthocyanins) provided beneficial physiological and metabolic responses during 4 h of indoor constant power cycling in a male amateur Ironman athlete 3 weeks before a competition. Future work is required to address whether acute and chronic dosing strategies with New Zealand blackcurrant provide a nutritional ergogenic effect for Ironman athletes to enhance swimming, cycling and running performance.

Comparison of low-fat chocolate flavoured milk to the standard practice of care as a recovery intervention in Ironman athletes: A randomised control trial

Comparison of low-fat chocolate flavoured milk to the standard practice of care as a recovery intervention in Ironman athletes: A randomised control trial

Effect of Stress on Cardiorespiratory Synchronization of Ironman Athletes.

The aim of this paper is to investigate the cardiorespiratory synchronization in athletes subjected to extreme physical stress combined with a cognitive stress tasks. ECG and respiration were measured in 14 athletes before and after the Ironman competition. Stroop test was applied between the measurements before and after the Ironman competition to induce cognitive stress. Synchrogram and empirical mode decomposition analysis were used for the first time to investigate the effects of physical stress, induced by the Ironman competition, on the phase synchronization of the cardiac and respiratory systems of Ironman athletes before and after the competition. A cognitive stress task (Stroop test) was performed both pre- and post-Ironman event in order to prevent the athletes from cognitively controlling their breathing rates. Our analysis showed that cardiorespiratory synchronization increased post-Ironman race compared to pre-Ironman. The results suggest that the amount of stress the athletes are recovering from post-competition is greater than the effects of the Stroop test. This indicates that the recovery phase after the competition is more important for restoring and maintaining homeostasis, which could be another reason for stronger synchronization.

Echocardiographic Pulmonary to Left Atrial Ratio (ePLAR): A Comparison Study between Ironman Athletes, Age Matched Controls and A General Community Cohort.

Background: During exercise there is a proportionally lower rise in systemic and pulmonary pressures compared to cardiac output due to reduced vascular resistance. Invasive exercise data suggest that systemic vascular resistance reduces more than pulmonary vascular resistance. The aim of this study was the non-invasive assessment of exercise hemodynamics in ironman athletes, compared with an age matched control group and a larger general community cohort. Methods: 20 ironman athletes (40 ± 11 years, 17 male) were compared with 20 age matched non-athlete controls (43 ± 7 years, 10 male) and a general community cohort of 230 non-athletes individuals (66 ± 11 years, 155 male), at rest and after maximal-symptom limited treadmill exercise stress echocardiography. Left heart parameters (mitral E-wave, e’-wave and E/e’) and right heart parameters (tricuspid regurgitation maximum velocity and right ventricular systolic pressure), were used to calculate the echocardiographic Pulmonary to Left Atrial Ratio (ePLAR) value of the three groups. Results: Athletes exercised for 12.2 ± 0.53 min, age matched controls for 10.1 ± 2.8 min and general community cohort for 8.3 ± 2.6 min. Mitral E/e’ rose slightly for athletes (0.9 ± 1.8), age matched controls (0.6 ± 3.0) and non-athletes (0.4 ± 3.2). Right ventricular systolic pressure increased significantly more in athletes than in both non-athlete cohorts (35.6 ± 17 mmHg vs. 20.4 ± 10.8 mmHg and 18 ± 9.6 mmHg). The marker of trans-pulmonary gradient, ePLAR, rose significantly more in athletes than in both non-athlete groups (0.15 ± 0.1 m/s vs. 0.07 ± 0.1 m/s). Conclusions: Pulmonary pressures increased proportionally four-fold compared with systemic pressures in ironman athletes. This increase in pulmonary vascular resistance corresponded with a two-fold increase in ePLAR. These changes were exaggerated compared with both non-ironman cohorts. Such changes have been previously suggested to lead to right ventricle dysfunction, arrhythmias and sudden cardiac death.

Peak Fat Oxidation is not Independently Related to Ironman Performance in Women.

The aim of the present study was to investigate if peak fat oxidation rate (PFO) is related to Ironman performance in female athletes. Thirty-six female Ironman athletes (age: 34±1 yrs, [21-45 yrs.] SEM [Range]) with a BMI of 22.1±2.0 kg/m2 [18.8-28.4 kg/m2], a body fat percentage of 24.8±1.0% [9.0-37.0%] and a V̇O2peak of 53.0±1.3 ml/min/kg [36.5-70.5 ml/min/kg] were tested in the laboratory prior to the Ironman Copenhagen 2017. Race time ranged from 9:17:07 to 15:23:48 with mean race time being 11:57:26 h:min:s (717 min). By simple linear regression analyses we found associations between race time and P FO (r2=0.22, p<0.005), V̇O2peak (r2=0.65, p<0.0001) and the relative exercise intensity eliciting PFO (Fatmax) (r2=0.35, p=0.0001). Furthermore, associations were found between race time and body fat percentage (r2=0.44, p<0.0001) and age (r2=0.16, p<0.05). By means of multiple regression analysis, V̇O2peak was the only statistically significant variable explaining 64% of the variation in race time (adj. r2=0.64, p<0.005). In conclusion, these results demonstrate that PFO is not independently related to Ironman performance in a heterogeneous group of female athletes. Interestingly, V̇O2peak alone was able to predict 64% of the variation in Ironman race times.

Trans-Pulmonary Haemodynamics Using Exercise Stress Echocardiography Pulmonary to Left Atrial Ratio (ePLAR): A Comparison between Ironman Athletes, a Small Group of Age-Matched Controls, and a Large-Group General Community Cohort

Trans-Pulmonary Haemodynamics Using Exercise Stress Echocardiography Pulmonary to Left Atrial Ratio (ePLAR): A Comparison between Ironman Athletes, a Small Group of Age-Matched Controls, and a Large-Group General Community Cohort

Maximal Fat Oxidation is Related to Performance in an Ironman Triathlon.

The aim of the present study was to investigate the relationship between maximal fat oxidation rate (MFO) measured during a progressive exercise test on a cycle ergometer and ultra-endurance performance. 61 male ironman athletes (age: 35±1 yrs. [23-47 yrs.], with a BMI of 23.6±0.3 kg/m2 [20.0-30.1 kg/m2], a body fat percentage of 16.7±0.7% [8.4-30.7%] and a VO2peak of 58.7±0.7 ml/min/kg [43.9-72.5 ml/min/kg] SEM [Range]) were tested in the laboratory between 25 and 4 days prior to the ultra-endurance event, 2016 Ironman Copenhagen. Simple bivariate analyses revealed significant negative correlations between race time and MFO (r2=0.12, p<0.005) and VO2peak (r2=0.45, p<0.0001) and a positive correlation between race time and body fat percentage (r2=0.27, p<0.0001). MFO and VO2peak were not correlated. When the significant variables from the bivariate regression analyses were entered into the multiple regression models, VO2peak and MFO together explained 50% of the variation observed in race time among the 61 Ironman athletes (adj R2=0.50, p<0.001). These results suggests that maximal fat oxidation rate exert an independent influence on ultra-endurance performance (>9 h). Furthermore, we demonstrate that 50% of the variation in Ironman triathlon race time can be explained by peak oxygen uptake and maximal fat oxidation.

Is Marathon Training Harder than the Ironman Training? An ECO-method Comparison.

Purpose: To compare the absolute and relative training load of the Marathon (42k) and the Ironman (IM) training in recreational trained athletes.Methods: Fifteen Marathoners and Fifteen Triathletes participated in the study. Their performance level was the same relative to the sex's absolute winner at the race. No differences were presented neither in age, nor in body weight, height, BMI, running VO2max max, or endurance training experience (p > 0.05). They all trained systematically for their respective event (IM or 42k). Daily training load was recorded in a training log, and the last 16 weeks were compared. Before this, gas exchange and lactate metabolic tests were conducted in order to set individual training zones. The Objective Load Scale (ECOs) training load quantification method was applied. Differences between IM and 42k athletes' outcomes were assessed using Student's test and significance level was set at p < 0.05.Results: As expected, Competition Time was significantly different (IM 11 h 45 min ± 1 h 54 min vs. 42k 3 h 6 min ± 28 min, p < 0.001). Similarly, Training Weekly Avg Time (IM 12.9 h ± 2.6 vs. 42k 5.2 ± 0.9), and Average Weekly ECOs (IM 834 ± 171 vs. 42k 526 ± 118) were significantly higher in IM (p < 0.001). However, the Ratio between Training Load and Training Time was superior for 42k runners when comparing ECOs (IM 65.8 ± 11.8 vs. 42k 99.3 ± 6.8) (p < 0.001). Finally, all ratios between training time or load vs. Competition Time were superior for 42k (p < 0.001) (Training Time/Race Time: IM 1.1 ± 0.3 vs. 42k 1.7 ± 0.5), (ECOs Training Load/Race Time: IM 1.2 ± 0.3 vs. 42k 2.9 ± 1.0).Conclusions: In spite of IM athletes' superior training time and total or weekly training load, when comparing the ratios between training load and training time, and training time or training load vs. competition time, the preparation of a 42k showed to be harder.

In Race Nutritional Strategies Comparing Ironman Wisconsin Athletes to Ironman World Championship Athletes

PURPOSE: The purpose of the current investigation was to compare the nutritional plans of Ironman Wisconsin athletes to elite Ironman World Championship athletes and to determine if differences exist between the two groups. METHODS: Athletes competing in Ironman triathlons were surveyed at Ironman Wisconsin (N = 73) and the Ironman World Championships (N = 79) to determine their in-race nutrition plans. Unpaired t-tests were run to examine the differences in overall finish time, calories consumed per hour on the bike, fluid consumed while biking, and caffeine consumption during the biking portion of the race. RESULTS: Athletes participating at the Ironman World Championships consumed significantly more (p < .01) calories per hour on the bike compared to Wisconsin Ironman athletes (299.9 kcal +/- 126.6; 239.5 kcal +/- 130.5, respectively). Ironman World Championships athletes consumed significantly (p < .01) more fluid on the bike compared to Wisconsin Ironman athletes (3827 mLs +/- 1693; 3327 mLs +/- 1874, respectively). Ironman World Championship athletes consumed significantly more (p < .01) caffeine while biking in comparison to Ironman Wisconsin athletes (110.7 mg +/- 172; 65.9 mg +/- 100.8, respectively). CONCLUSIONS: Ironman World Championships athletes consumed higher amounts of calories per hour, fluid, and caffeine during the bike in comparison to the Ironman Wisconsin athletes. This suggests that elite Ironman athletes consume more calories, caffeine, and fluids during their races when compared to average Ironman athletes, and hence increased calorie and caffeine consumption may contribute to faster performances for the elite athletes.

Left Ventricular Function and Physiological Performance in Female Ironman Athletes and Female Police Officers.

Data about physiological performance of female ironman triathletes are rare. However, some studies have reported this endurance sport may cause damage to the right or left ventricles, even in females. The goal of this study was to assess prospectively the right/left ventricular function and physiological performance in female athletes (middle- and long ironman distance) and to compare the findings to female federal police officers. A total of 33 female triathletes and 37 female police officers were examined using spiro-ergometry and echocardiography. Female triathletes achieved VO2max 52.8 ± 5.7 ml/kg(-1)·min(-1), and police officers 35.3 ± 6.5 ml/kg(-1)·min(-1) In athletes, left ventricular end-diastolic diameter was 4.4 ± 0.3 cm and in police officers 4.5 ± 0.4 cm, and the left ventricular muscle mass index was 85.8 g/m(2 )± 18.7 in athletes and in police officers 72.0 g/m(2 )± 9.1. Right ventricular area change among athletes was 49.4 ± 8.5%, and in police officers 46.0 ± 6.9%. The performance date of female triathletes can be used as training prescription for leisure female triathletes, when middle or long distances in triathlon competitions are planned. No right or left ventricular dysfunction was found despite long training and finishing of long distance competitions: non-elite athletes, 5.4 ± 2.8 years of triathlon competitions; elite athletes, 7.6 ± 5.8 years.

The COMT val158met polymorphism in ultra-endurance athletes

Chronic levels of physical activity have been associated with increased dopamine (D2) receptors resulting in increased sensitivity to dopamine release. The catechol-O-methyltransferase enzyme, responsible for dopamine degradation, contains a functional polymorphism, which plays an important role in dopamine regulation within the prefrontal cortex. This polymorphism has previously been shown to affect human cognition and personality. However, the effect of this polymorphism has not been shown in ultra-endurance athletes. AimTo examine the association of the COMT val158met variant with personality traits (harm avoidance, novelty seeking, reward dependence, resilience) and psychological distress (K10) of habitual physically active Ironman athletes compared to recreationally active controls. Methods51 ultra-endurance Ironman athletes and 56 recreationally active controls were genotyped for the catechol-O-methyltransferase val158met polymorphism. Of the 107 participants, 55 ultra-endurance athletes and 32 recreationally active controls completed online personality questionnaires (harm avoidance, novelty seeking, reward dependence, resilience) and a psychological distress questionnaire (K10). ResultsThe personality trait, harm avoidance (p=0.001) and psychological distress (p=0.003) were significantly lower in Ironman athlete participants. Novelty seeking was significantly higher (p=0.02) in Ironman athlete participants with a significantly higher (p=0.04) score in Met158 homozygous allele carriers. ConclusionChronic levels of physical activity, as seen in ultra-endurance athletes, show increased novelty seeking scores in Met158 homozygous allele carriers.

Endurance sport and "cardiac injury": a prospective study of recreational ironman athletes.

Background: Participation in triathlon competitions has increased in recent years. Many studies have described left or right ventricular injury in endurance athletes. The goal of this study was to examine the right and left ventricular cardiac structures and function and dynamic cardio-pulmonary performance in a large cohort of middle- and long-distance triathletes. Methods: 87 triathletes (54 male and 33 female) were examined using spiroergometry and echocardiography. The inclusion criterion was participation in at least one middle- or long distance triathlon. Results: Male triathletes showed a maximum oxygen absorption of 58.1 ± 8.6 mL/min/kg (female triathletes 52.8 ± 5.7 mL/min/kg), maximum ergometer performance of 347.8 ± 49.9 W (female triathletes 264.5 ± 26.1 W). Left ventricular ejection fraction (EF) was normal (male triathletes EF: 61.9% ± 3%, female triathletes EF: 63.0% ± 2.7%) and systolic right ventricular area change fraction (RV AFC%) showed normal values (males RV AFC%: 33.5% ± 2.2%, females 32.2% ± 2.8%). Doppler indices of diastolic function were normal in both groups. With respect to the echocardiographic readings the left ventricular mass for males and females were 217.7 ± 41.6 g and 145.9 ± 31.3 g, respectively. The relative wall thickness for males was 0.50 ± 0.07, whereas it was 0.47 ± 0.09 for females. The probability of left ventricular mass >220 g increased with higher blood pressure during exercise (OR: 1.027, CI 1.002–1.052, p = 0.034) or with higher training volume (OR: 1.23, CI 1.04–1.47, p = 0.019). Conclusions: Right or left ventricular dysfunction could not be found, although the maximal participation in triathlon competitions was 29 years. A left ventricular mass >220 g is more likely to occur with higher arterial pressure during exercise and with a higher training volume.

Right Ventricle Best Predicts the Race Performance in Amateur Ironman Athletes

The ironman (IM) triathlon is a popular ultraendurance competition, consisting of 3.8 km of swimming, 180.2 km of cycling, and 42.2 km of running. The aim of this study was to investigate the predictors of IM race time, comparing echocardiographic findings, anthropometric measures, and training characteristics. Amateur IM athletes (ATHL) participating in the Zurich IM race in 2010 were included. Participants were examined the day before the race by a comprehensive echocardiographic examination. Moreover, anthropometric measurements were obtained the same day. During the 3 months before the race, each IM-ATHL maintained a detailed training diary. Recorded data were related to total IM race time. Thirty-eight IM finishers (mean ± SD age = 38 ± 9 yr, 32 men [84%]) were evaluated. Total race time was 684 ± 89 min (mean ± SD). For right ventricular fractional area change (45% ± 7%, Spearman ρ = -0.33, P = 0.05), a weak correlation with race time was observed. Race performance exhibited stronger associations with percent body fat (15.2 ± 5.6%, ρ = 0.56, P = 0.001), speed in running training (11.7 ± 1.2 km · h(-1), ρ = -0.52, P = 0.002), and left ventricular myocardial mass index (98 ± 24 g · m(-2), ρ = -0.42, P = 0.009). The strongest association was found between race time and right ventricular end-diastolic area (22 ± 4 cm2, ρ = -0.64, P < 0.0001). In multivariate analysis, right ventricular end-diastolic area (β = -16.7, 95% confidence interval = -27.3 to -6.1, P = 0.003) and percent body fat (β = 6.8, 95% confidence interval = 1.1-12.6, P = 0.02) were independently predictive of IM race time. In amateur IM-ATHL, RV end-diastolic area and percent body fat were independently related to race performance. RV end-diastolic area was the strongest predictor of race time. The role of the RV in endurance exercise may thus be more important than previously thought and needs to be further studied.

Somatotype, training and performance in Ironman athletes

The aim of this study was to describe the physiques of Ironman athletes and the relationship between Ironman's performance, training and somatotype. A total of 165 male and 22 female competitors of the Ironman Switzerland volunteered in this study. Ten anthropometric dimensions were measured, and 12 training and history variables were recorded with a questionnaire. The variables were compared with the race performance. The somatotype was a strong predictor of Ironman performance (R=0.535; R2=0.286; sign. p<0.001) in male athletes. The endomorphy component was the most substantial predictor. Reductions in endomorphy by one standard deviation as well as an increased ectomorphy value by one standard deviation lead to significant and substantial improvement in Ironman performance (28.1 and 29.8 minutes, respectively). An ideal somatotype of 1.7–4.9–2.8 could be established. Age and quantitative training effort were not significant predictors on Ironman performance. In female athletes, no relationship between somatotype, training and performance was found. The somatotype of a male athlete defines for 28.6% variance in Ironman performance. Athletes not having an ideal somatotype of 1.7–4.9–2.8 could improve their performance by altering their somatotype. Lower rates in endomorphy, as well as higher rates in ectomorphy, resulted in a significant better race performance. The impact of somatotype was the most distinguished on the run discipline and had a much greater impact on the total race time than the quantitative training effort. These findings could not be found in female athletes.

Structural and functional cardiac alterations in Ironman athletes: New insights into athlete's heart remodeling

The structure of the heart of athletes (ATHL) may differ from that of non-athletes, provided that a regular training of sufficient intensity and duration is performed [1]. Preparation for an Ironman (IM) triathlon consists of extreme endurance training with both dynamic and static components. This may impact cardiac remodeling more than typical of an athlete's heart. The available echocardiographic data on morphologic and functional cardiac alterations in IM-ATHL are limited and no data exist on application of echocardiographic criteria for specific cardiomyopathies to the remodeled hearts of these ATHL.

Pulmonary Edema in Healthy Subjects in Extreme Conditions

There are several pieces of evidence showing occurrence of pulmonary edema (PE) in healthy subjects in extreme conditions consisting of extreme psychophysical demand in normal environment and psychophysical performances in extreme environment. A combination of different mechanisms, such as mechanical, hemodynamic, biochemical, and hypoxemic ones, may underlie PE leading to an increase in lung vascular hydrostatic pressure and lung vascular permeability and/or a downregulation of the alveolar fluid reabsorption pathways. PE can be functionally detected by closing volume measurement and lung diffusing capacity test to different gases or directly visualized by multiple imaging techniques. Among them chest ultrasonography can detect and quantify the extravascular lung water, creating “comet-tail” ultrasound artefacts (ULCs) from water-thickened pulmonary interlobular septa. In this paper the physiopathological mechanisms of PE, the functional and imaging techniques applied to detect and quantify the phenomenon, and three models of extreme conditions, that is, ironman athletes, climbers and breath-hold divers, are described.

Upper Body Skinfold Thickness is Related to Race Performance in Male Ironman Triathletes

We investigated the association between skinfold thickness and race performance in male and female Ironman triathletes. Skinfold thicknesses at 8 sites and percent body fat were correlated to total race time including the split times for the 3 sub disciplines, for 27 male and 16 female Ironman athletes. In the males, percent body fat (r=0.76; p<0.0001), the sum of upper body skinfolds (r=0.75; p<0.0001) and the sum of all 8 skinfolds (r=0.71; p<0.0001) were related to total race time. Percent body fat (r=-0.67; p<0.001), the sum of upper body skinfolds (r=-0.63, p=0.0004) and the sum of all 8 skinfolds (r=-0.59; p<0.001) were also associated with speed in cycling during the race. In the females, none of the skinfold thicknesses showed an association with total race time, average weekly training volume or speed in the sub disciplines in the race. The results of this study indicate that low skinfold thicknesses of the upper body are related to race performance in male Ironman triathletes, but not in females.

Sources of Motivation in Introductory and Advanced Triathlon Events

A pilot study surveyed triathlon participants to analyze sources of motivation. Challenge was a significant motivation source for Ironman athletes. Conversely, other sources were more important in a novice triathlon event. Insights from the pilot study were used to improve the survey design. PURPOSE: Participants in introductory and advanced triathlon events were surveyed to determine the contribution of: 1) Challenge, 2) Competition, 3) Lifestyle, 4) Social influences, 5) Family influences, 6) Nature, and 7) Spirituality to motivation for participation. METHODS: The introductory event was the Ironman Challenge (IMC), a three-week long self-directed triathlon designed to encourage physical activity and triathlon participation among university staff, students, and community members. The advanced event was the 2009 Ironman Coeur d' Alene triathlon (CDA). Survey information was solicited from convenience samples of participants at both events (IMC: nfemales=26, nmales=16; CDA: nfemales=14, nmales=42). Survey respondents were asked to rank order their top three sources of motivation. RESULTS: Several respondents did not rank order, but did indicate, their top three motivation sources. Consequently, frequency distributions were created to analyze the survey responses (see Table 1).TABLE 1: The frequencies of motivation sources for IMC and CDA are summarized.CONCLUSION: However, without rank order data, it is unknown whether Challenge was the most important source of motivation or consistently in the top three. Respondents from both events cited Challenge most frequently. Further research should explore the relationship between the motivation types with other physical fitness events.

82 Suppression of salivary IgA secretion rate pre and post intense short term exercise in half ironman athletes

82 Suppression of salivary IgA secretion rate pre and post intense short term exercise in half ironman athletes

Hemolysis during triathlon races: its relation to race distance.

Ninety-five triathletes were evaluated for evidence of hemolysis during triathlon races of two different distances. Thirty competitors (11 males, 19 females) were studied before and after the United States Triathlon Series (USTS) National Championship Race (1.5K swim, 40K bike, and 10K run). Pre- and post-race venous blood samples showed that 93% of the USTS athletes had decreased serum haptoglobin, post-race (mean decrease = 20%). Seven of 30 of the USTS triathletes (3 males, 4 females) were found to have occult blood in their urine, post-race. Only two of the USTS triathletes (1 male, 1 female) were anemic as judged by pre-race hemoglobin levels. Similar data were collected on 65 triatheletes (46 males, 19 females) at the Hawaii IRONMAN Triathlon World Championship (3.9K swim, 180.2K bike, and 42.2K run). Pre- and post-race venous blood samples showed that 95% of the IRONMAN athletes had decreases in serum haptoglobin, post-race (mean decrease = 32%). Occult blood was found in the post-race urine of 19 (12 males, 7 females) of the IRONMAN competitors. Nineteen IRONMAN triathletes (18 males, 1 female) were judged to be anemic from pre-race hemoglobin measurements. Data from two different length triathlons suggest that nearly all triathletes break down red blood cells during a race, and that the extent of the hemolysis is related to race distance.