Is iron treatment beneficial in, iron-deficient but non-anaemic (IDNA) endurance athletes? A systematic review and meta-analysis.

PURPOSE: The aim of this study was to determine whether iron treatments improve the iron status and aerobic capacity of iron deficient non-anaemic endurance athletes. METHOD: A meta-analysis of studies that investigated the effects of iron treatment on serum ferritin (sFer), serum iron (sFe), transferrin saturation (Tsat), haemoglobin concentration ([Hb]) and (VO(2max)). Seventeen eligible studies were identified from online databases. RESULTS: Analysis of pooled data indicated that iron treatments had a large effect on improving sFer (Hedges' g=1.088, 95% CI 0.914 to 1.263, p<0.001), sFe (Hedges' g=1.004, 95% CI 0.828 to 1.181, p<0.001) and Tsat (Hedges g=0.741, 95% CI 0.564 to 0.919, p<0.001) and a moderate effect on improving [Hb] (Hedges' g=0.695, 95% CI 0.533 to 0.836, p<0.001) and (VO(2max)) (Hedges' g=0.610, 95% CI 0.399 to 0.821, p<0.001). Regression analysis revealed a significant interaction between the effect of iron treatment on sFer and treatment duration, suggesting treatments that lasted beyond 80 days appear to have the least effect on sFer. CONCLUSIONS: These results indicate iron treatments improve the iron status and aerobic capacity of iron deficient non-anaemic endurance athletes.

Effect of Intravenous Iron on Aerobic Capacity and Iron Metabolism in Elite Athletes.

PURPOSE: Iron-deficient athletes are often treated with long-term, low-dose iron therapy. Such treatments may be efficacious in correcting iron deficiency; however, the effect on acute and chronic iron metabolism and subsequent endurance capacity is less clear. METHODS: Fifteen national and international standard runners were identified as iron deficient nonanemic (IDNA) and assigned to either an intravenous iron treatment group or placebo group. Participants completed three exercise tests to volitional exhaustion, as follows: before treatment, within 24 h, and 4 wk after treatment. RESULTS: Serum ferritin, serum iron, and transferrin saturation were significantly improved in the iron group after intervention and compared with those in placebo (P < 0.05). Hepcidin levels were significantly greater before and after exercise after the iron injection (P < 0.05), and this was independent of changes in interleukin-6. There were no differences between groups in red cell indices, total hemoglobin mass, V˙O2max, submaximal blood lactate, running economy, RPE, or time to exhaustion (P > 0.05). CONCLUSIONS: A single 500-mg intravenous iron injection is effective for improving iron status for at least 4 wk, but this does not lead to improved aerobic capacity. This investigation suggests that iron availability supersedes inflammation in the regulation of hepcidin in IDNA endurance athletes after acute intravascular iron injection treatment.

Comparison of three current sets of electrocardiographic interpretation criteria for use in screening athletes.

BACKGROUND: An increasing number of sporting bodies report unacceptably high levels of false-positive ECGs when undertaking pre-participation cardiac screening. To address this issue, modified ECG interpretation criteria have become available for use within athletes. OBJECTIVE: This study assessed the accuracy of the new 2014 'Refined Criteria' against the 2013 Seattle Criteria and the 2010 European Society of Cardiology (ESC) recommendations in a cohort of Arabic, black and Caucasian athletes. METHODS: 2491 male athletes (1367 Arabic, 748 black and 376 Caucasian) undertook pre-participation screening including a 12-lead ECG, with further investigation(s) upon indication. RESULTS: Ten athletes (0.4%) were identified with cardiac pathology; seven with hypertrophic cardiomyopathy (HCM; five black and two Arabic) and three Arabs with Wolff-Parkinson-White syndrome (WPW). All three ECG criteria were 100% sensitive identifying all cases of HCM and WPW. The 2014 Refined Criteria reduced (p<0.0001) the prevalence of an abnormal ECG to 5.3% vs 11.6% (Seattle Criteria) and 22.3% (2010 ESC recommendations). The 2014 Refined Criteria significantly (p<0.0001) improved specificity (94.0%) across all ethnicities compared with the Seattle Criteria (87.5%) and ESC recommendations (76.6%). Black athletes continue to present a higher prevalence (p<0.0001) of abnormal ECGs compared with Arabic and Caucasian athletes (10% vs 3.6% and 2.1%). CONCLUSIONS: The 2014 Refined Criteria for athlete ECG interpretation outperformed both the 2013 Seattle Criteria and the 2010 ESC recommendations by significantly reducing the number of false-positive ECGs in Arabic, black and Caucasian athletes while maintaining 100% sensitivity for serious cardiac pathologies.

Systematic echocardiography is not efficacious when screening an ethnically diverse cohort of athletes in West Asia.

BACKGROUND: The clinical and economic value of including systematic echocardiography (ECHO) alongside the 12-lead electrocardiograpm (ECG) when undertaking pre-participation screening in athletes has not been examined, yet several sporting organistations recommend its inclusion. DESIGN: To examine the efficacy of systematic ECHO alongside the ECG, to identify sudden cardiac death (SCD) disease and to provide a cost-analysis of a government-funded pre-participation screening programme. METHODS: A total 1628 athletes presented for cardiological consultation, ECG, and ECHO as standard, with further cardiac examinations performed if necessary to confirm or exclude pathology. The efficacy of systematic ECHO was compared to an ECG-led programme, with ECHO reserved as a follow-up examination. RESULTS: To screen 1628 athletes with ECG and ECHO cost US$743,996. There were 54 24-h-blood pressure/ECG Holter recordings, 62 exercise tests, 25 CMRs, two electrophysiological studies, and two genetic tests, which cost US$67,734: total US$811,730. Eight athletes (0.5%) were identified with hypertrophic cardiomyopathy (HCM) and two (0.1%) with Wolff-Parkinson-White syndrome. The cost per identifed athlete was US$81,173. All 10 athletes presented an abnormal ECG. No athlete diagnosed with HCM was identified by ECHO in isolation. When adopting a ECG-led screening protocol, 15% of athletes required ECHO as a follow-up examination, resulting in a US$380,600 cost reduction (47% saving), with the cost per diagnosis reduced to US$43,113. CONCLUSIONS: Athletes diagnosed with a disease associated with SCD were identified via an abnormal ECG and/or physical examination, personal symptoms, or family history. Screening athletes with systematic ECHO is not economically or clinically effective.

ECG and morphologic adaptations in Arabic athletes: are the European Society of Cardiology's recommendations for the interpretation of the 12-lead ECG appropriate for this ethnicity?

AIMS: To examine the cardiac structure and function of Arabic athletes and to establish if the European Society of Cardiology (ESC) guidelines for the interpretation of an athlete's ECG are applicable to this ethnicity. METHODS: 600 high-level Arabic, 415 Black African, 160 Caucasian male athletes (exercising ≥6 h/week) and 201 Arabic controls presented for ECG and echocardiographic screening. RESULTS: 9 athletes (0.7%) were identified with a cardiac pathology associated with sudden cardiac death. Two Arabics (0.3%) and five Black Africans (1.2%) were diagnosed with hypertrophic cardiomyopathy; a prevalence four times greater in Black African compared to Arabic athletes. Arabic athletes had significantly greater (p<0.05) left ventricular (LV) end-diastolic diameters, maximal LV wall thicknesses and LV mass compared with controls; yet were significantly smaller than Black African and Caucasian athletes. The percentage of athletes demonstrating LV hypertrophy (≥12 mm) was comparable between Arabic, Black African and Caucasian populations (0.5%, 0.5% and 0.6%, respectively). There was no difference in the frequency of an uncommon and training-unrelated ECG between Arabic and Caucasian. However, Black Africans demonstrated a significantly greater prevalence than Arabic and Caucasian athletes (20% vs 8.4% and 6.9%, p<0.001); specifically more right/left atrial enlargement and T wave inversion. CONCLUSIONS: Arabic athletes present significantly smaller cardiac dimensions than Black African and Caucasian athletes. There was no significant difference between the frequency of an uncommon and training-unrelated ECG between Arabic and Caucasian athletes. Therefore, the use of ESC guidelines for the interpretation of an athlete's ECG is clinically relevant and acceptable for use within Arabic athletes.

Challenges in Maintaining Emotion Regulation in a Sleep and Energy Deprived State Induced by the 4800Km Ultra-Endurance Bicycle Race; The Race Across AMerica (RAAM).

Multiday ultra-endurance races present athletes with a significant number of physiological and psychological challenges. We examined emotions, the perceived functionality (optimal-dysfunctional) of emotions, strategies to regulate emotions, sleep quality, and energy intake-expenditure in a four-man team participating in the Race Across AMerica (RAAM); a 4856km continuous cycle race. Cyclists reported experiencing an optimal emotional state for less than 50% of total competition, with emotional states differing significantly between each cyclist over time. Coupled with this emotional disturbance, each cyclist experienced progressively worsening sleep deprivation and daily negative energy balances throughout the RAAM. Cyclists managed less than one hour of continuous sleep per sleep episode, high sleep latency and high percentage moving time. Of note, actual sleep and sleep efficiency were better maintained during longer rest periods, highlighting the importance of a race strategy that seeks to optimise the balance between average cycling velocity and sleep time. Our data suggests that future RAAM cyclists and crew should: 1) identify beliefs on the perceived functionality of emotions in relation to best (functional-optimal) and worst (dysfunctional) performance as the starting point to intervention work; 2) create a plan for support sufficient sleep and recovery; 3) create nutritional strategies that maintain energy intake and thus reduce energy deficits; and 4) prepare for the deleterious effects of sleep deprivation so that they are able to appropriately respond to unexpected stressors and foster functional working interpersonal relationships. Key PointsCompleting the Race Across AMerica (RAAM); a 4856km continuous cycle race associated with sleep disturbance, an energy-deficient state, and experiencing intense unwanted emotions.Cyclists reported experiencing an optimal emotional state for less than 50% of total competition and actual sleep and sleep efficiency was better maintained during longer rest periods.We suggest that future RAAM cyclists and crew should:Identify individual beliefs on the perceived functionality of emotional states in relation to best (optimal) and worst (dysfunctional) performance as the starting point to identifying if emotion regulation strategies should be initiated.Plan for enhanced sleep and recovery not just plan and train for maintaining a high average velocity;Create nutritional strategies that maintain energy intake and thus reduce energy deficits;Psychologically prepare cyclists and crew for the deleterious effects of sleep deprivation so that they both are able to appropriately respond to unexpected stressors and foster functional interpersonal working relationships.

A case study of an iron-deficient female Olympic 1500-m runner.

This case study examines the impact of low serum ferritin (sFe) on physiological assessment measures and performance in a young female 1500-m runner undertaking approximately 95-130 km/wk training. The study spans 4 race seasons and an Olympic Games. During this period, 25 venous blood samples were analyzed for sFe and hemoglobin (Hb); running economy, VO(2max), and lactate threshold were measured on 6 occasions separated by 8-10 mo. Training was carefully monitored including 65 monitored treadmill training runs (targeting an intensity associated with the onset of blood lactate accumulation) using blood lactate and heart rate. Performances at competitive track events were recorded. All data were compared longitudinally. Mean sFe was 24.5 ± 7.6 µg/L (range 10-47), appearing to be in gradual decline with the exception of 2 data points (37 and 47 µg/L) after parenteral iron injections before championships, when the lowest values tended to occur, coinciding with peak training volumes. Each season, 1500-m performance improved, from 4:12.8 in year 1 to 4:03.5 in year 4. VO(2max) (69.8 ± 2.0 mL · kg(-1) · min(-1)) and running economy (%VO(2max) at a fixed speed of 16 km/h; max 87.8%, min 80.3%) were stable across time and lactate threshold improved (from 14 to 15.5 km/h). Evidence of anemia (Hb <12 g/dL) was absent. These unique data demonstrate that in 1 endurance athlete, performance can continue to improve despite an apparent iron deficiency. Raising training volume may have caused increased iron utilization; however, the effect of this on performance is unknown. Iron injections were effective in raising sFe in the short term but did not appear to affect the long-term pattern.

Do big athletes have big hearts? Impact of extreme anthropometry upon cardiac hypertrophy in professional male athletes.

AIM: Differentiating physiological cardiac hypertrophy from pathology is challenging when the athlete presents with extreme anthropometry. While upper normal limits exist for maximal left ventricular (LV) wall thickness (14 mm) and LV internal diameter in diastole (LVIDd, 65 mm), it is unknown if these limits are applicable to athletes with a body surface area (BSA) >2.3 m(2). PURPOSE: To investigate cardiac structure in professional male athletes with a BSA>2.3 m(2), and to assess the validity of established upper normal limits for physiological cardiac hypertrophy. METHODS: 836 asymptomatic athletes without a family history of sudden death underwent ECG and echocardiographic screening. Athletes were grouped according to BSA (Group 1, BSA>2.3 m(2), n=100; Group 2, 2-2.29 m(2), n=244; Group 3, <1.99 m(2), n=492). RESULTS: There was strong linear relationship between BSA and LV dimensions; yet no athlete with a normal ECG presented a maximal wall thickness and LVIDd greater than 13 and 65 mm, respectively. In Group 3 athletes, Black African ethnicity was associated with larger cardiac dimensions than either Caucasian or West Asian ethnicity. Three athletes were diagnosed with a cardiomyopathy (0.4% prevalence); with two athletes presenting a maximal wall thickness >13 mm, but in combination with an abnormal ECG suspicious of an inherited cardiac disease. CONCLUSION: Regardless of extreme anthropometry, established upper limits for physiological cardiac hypertrophy of 14 mm for maximal wall thickness and 65 mm for LVIDd are clinically appropriate for all athletes. However, the abnormal ECG is key to diagnosis and guides follow-up, particularly when cardiac dimensions are within accepted limits.

Cardiac adaptation to acute and chronic participation in endurance sports.

The pervasive public health message is that moderate amounts of endurance exercise help maintain optimal health and reduce cardiovascular risk. While not enough people meet national physical activity guidelines, there are some at the opposite end of the activity spectrum who far exceed the recommended 'dose' of exercise. The cardiovascular health consequences of single and/or multiple (lifelong) 'doses' of high-volume endurance exercise are currently being debated. Recent commentaries, case reports and case series data have posed the question whether you can 'overdose on exercise', and that is the focus of this brief review.

Physiological correlates of emotion-regulation during prolonged cycling performance.

We proposed that experiencing unpleasant emotions during performance represents unsuccessful emotion-regulatory efforts, and that such effort concurrently tax physiological resources. We used data from 2-h cycling trials (N = 28) at a power output equivalent to lactate threshold. Emotions were calculated before and during cycling with ongoing assessments of ventilation, respiratory quotient, heart rate, and oxygen uptake. Emotion data indicated significant changes over time with all participants reporting decreases in vigour and increases in fatigue, with 14 cases of concurrent increases in anger, depression, and tension. After grouping participants into positive and negative emotion groups, a time x unpleasant emotion group ANOVA indicated a significant interaction effect for changes in ventilation (F (6,21) = 3.09, P = .03, Partial Eta(2) = .47) over time, with no significant difference in other physiological variables or perceived exertion. Among athletes reporting negative emotions, ventilation increased during the middle section, whereas among athletes reporting positive emotions, ventilation increased shortly before completion. Findings suggest that regulating negative emotion is an effortful process taxing physiological substrates.

The effectiveness of compression garments and lower limb exercise on post-exercise blood pressure regulation in orthostatically intolerant athletes.

OBJECTIVE: Orthostatic intolerance (OI) may occur postexercise in normotensive individuals due to gravitational stress and removal of muscle pump. DESIGN: Six subjects performed 3 maximal bouts of exercise associated with (1) no intervention (CONTROL) (initial trial), (2) with use of lower limb compression garment (TROU), and (3) lower limb exercise (HEEL). SETTING: In each trial, 10 minutes of supine rest was followed by 10 minutes of standing before and immediately after maximal exercise. PARTICIPANTS: All subjects were OI during the CONTROL trial. INTERVENTIONS: In the TROU trial, the compression garment was worn during the supine and standing phases. In the HEEL trial, heel raises were performed every 60 seconds during standing periods. MAIN OUTCOME MEASURES: Systolic blood pressure and heart rate were continuously recorded, and stroke, cardiac output, and total peripheral resistance were estimated (PortAPres, TNO Biomedical Instrumentation, Amsterdam, the Netherlands). Positional changes were compared preexercise and postexercise in CONTROL, TROU, and HEEL via 2-way analysis of variance. RESULTS: All 6 subjects experienced OI in the CONTROL trial, but this was reduced to 2 after the HEEL and 1 after the TROU. Minor increases in systolic blood pressure (CONTROL, 3 +/- 11; TROU, 12 +/- 18; HEEL, 7 +/- 15 mm Hg) and heart rate (CONTROL, 10 +/- 12; TROU, 16 +/- 8; HEEL, 15 +/- 13 beats.min) were observed, but total peripheral resistance did not alter significantly during orthostasis postexercise (CONTROL, 0.462 +/- 0.351; TROU, 0.325 +/- 0.212; HEEL, 0.746 +/- 0.412 medical units). CONCLUSIONS: It seems that simple methods/practices adopted by athletes can have a positive impact on OI.

Clinical significance of cardiac damage and changes in function after exercise.

Acute bouts of ultraendurance exercise may result in the appearance of biomarkers of cardiac cell damage and a transient reduction in left ventricular function. The clinical significance of these changes is not fully understood. There seems to be two competing issues to be resolved. First, could prolonged endurance exercise produce a degree of cardiac stress and/or damage that results, during the short or long term, in deleterious consequences for cardiac health. Second, there is a clear need to educate those responsible for the medical care of endurance athletes about the possibility of a transient reduction in cardiac function and the appearance of cTnT/cTnI after an exercise. Minor elevations in cardiac troponins are commonplace after an endurance exercise in elite and recreational athletes and may occur alongside exercise-associated collapse. Misdiagnosis of myocardial injury and subsequent mismanagement can be unnecessarily expensive and psychologically damaging to the athlete. Diagnosis of myocardial injury after prolonged exercise should be made on the basis of all available information and not blood tests alone. The clinical significance of chronic exposure to endurance exercise is unknown. The development of myocardial fibrosis has been suggested as a long-term outcome to chronic exposure to repetitive bouts of endurance exercise and has been linked to an exercise-induced inflammatory process observed in an animal model. This hypothesis is supported by a limited number of studies reporting postmortem studies in athletes and an increased prevalence of complex arrhythmia in veteran athletes. Care is warranted in promoting this hypothesis without further detailed work, given the unequivocal link between exercise and mortality and morbidity. It would seem erroneous, however, to assume that a linear relationship exists between exercise volume and cardiac health.

Differentiation of RVOT-VT and ARVC in an elite athlete.

BACKGROUND: Differentiation of right ventricular outflow tract-ventricular tachycardia (RVOT-VT) and arrhythmogenic right ventricular cardiomyopathy (ARVC) can be problematic in athletes. The high incidence of sudden death as the first clinical manifestation in ARVC highlights the importance of correct diagnosis and treatment. We report on the case of RVOT-VT in an elite female sprinter, and we review the literature on ventricular tachycardia (VT) in the absence of structural heart disease and ARVC. DISCUSSION: Of patients who present with VT, 10% have no obvious structural disease. In the case of idiopathic VT from the RVOT and LVOT, the arrhythmia is monomorphic and generally not familial. In both disorders, the resting ECG has no identifiable abnormalities, and the echocardiogram and coronary angiography are usually normal. ARVC is a heart muscle disorder characterized by structural and functional abnormalities of the right ventricle due to a fibro-fatty replacement of the myocardium. The natural history of ARVC is considered to include four distinct phases. The early concealed phase of ARVC demonstrates ECG abnormalities concomitant to right and left ventricular dyskinesias. Differential diagnosis during this phase is problematic due to the presence of left bundle branch block morphology VT together with ECG anomalies commonly observed in athletes in RVOT-VT. Furthermore, long-standing VT in RVOT-VT may result in ventricular wall motion abnormalities mimicking ARVC. Radiofrequency ablation may be a valuable tool in the differential diagnosis, because this technique is highly effective in the treatment of RVOT-VT and of limited value in ARVC. Continued follow-up evaluation is an important for the confirmation of disease status after the diagnosis of idiopathic RVOT-VT.

Physiological and performance effects of low- versus mixed-intensity rowing training.

PURPOSE: To examine the impact of low-intensity and a mixture of low- and high-intensity training on physiological and performance responses in rowing. METHODS: Eighteen experienced rowers undertook a 12-wk program of 100% < or = lactate threshold (LT) training (LOW) or 70% training at < or = LT and 30% at halfway (50%Delta) between the V O2 at LT and V O2peak (MIX). Responses were assessed before and after training by a progressive exercise test to exhaustion; multiple "square-wave" rest-to-exercise transitions of 6-min duration at 50%Delta; and a maximal 2000-m ergometer time trial. RESULTS: Improvements (P < 0.001) in 2000-m ergometer performance and V O2peak occurred independently of groups (P = 0.8 and 0.42, respectively). LOW improved the power at LT (23.5 +/- 12.2 vs 5.1 +/- 5.0 W, P = 0.013) and power at a [blood lactate] of 4 mM (32.3 +/- 6.9 vs 13.1 +/- 3.7 W, P = 0.03) compared with MIX. The time constant and gain of the primary component were unchanged with training, whereas the gain of the V O2 slow component was reduced with training, but independently of group. CONCLUSIONS: Both LOW and MIX training programs improved performance and V O2peak by the same magnitude, whereas LOW attenuated the blood lactate response to a given exercise intensity more so than MIX.

The effects of a graduated aerobic exercise programme on cardiovascular disease risk factors in the NHS workplace: a randomised controlled trial.

BACKGROUND: Sufficient levels of physical activity provide cardio-protective benefit. However within developed society sedentary work and inflexible working hours promotes physical inactivity. Consequently to ensure a healthy workforce there is a requirement for exercise strategies adaptable to occupational time constraint. This study examined the effect of a 12 week aerobic exercise training intervention programme implemented during working hours on the cardiovascular profile of a sedentary hospital workforce. METHODS: Twenty healthy, sedentary full-time staff members of the North West London Hospital Trust cytology unit were randomly assigned to an exercise (n = 12; mean +/- SD age 41 +/- 8 years, body mass 69 +/- 12 kg) or control (n = 8; mean +/- SD age 42 +/- 8 years, body mass 69 +/- 12 kg) group. The exercise group was prescribed a progressive aerobic exercise-training programme to be performed 4 times a week for 8 weeks (initial intensity 65% peak oxygen consumption (VO2 peak)) and to be conducted without further advice for another 4 weeks. The control was instructed to maintain their current physical activity level. Oxygen economy at 2 minutes (2minVO2), 4 minutes (4minVO2), VO2 peak, systolic blood pressure (SBP), diastolic blood pressure (DBP), BMI, C-reactive protein (CRP), fasting glucose (GLU) and total cholesterol (TC) were determined in both groups pre-intervention and at 4 week intervals. Both groups completed a weekly Leisure Time Questionnaire to quantify additional exercise load. RESULTS: The exercise group demonstrated an increase from baseline for VO2 peak at week 4 (5.8 +/- 6.3 %) and 8 (5.0 +/- 8.7 %) (P < 0.05). 2minVO2 was reduced from baseline at week 4 (-10.2 +/- 10.3 %), 8 (-16.8 +/- 10.6 %) and 12 (-15.1 +/- 8.7 %), and 4minVO2 at week 8 (-10.7 +/- 7.9 %) and 12 (-6.8 +/- 9.2) (P < 0.05). There was also a reduction from baseline in CRP at week 4 (-0.4 +/- 0.6 mg.L-1) and 8 (-0.9 +/- 0.8 mg.L-1) (P < 0.05). The control group showed no such improvements. CONCLUSION: This is the first objectively monitored RCT to show that moderate exercise can be successfully incorporated into working hours, to significantly improve physical capacity and cardiovascular health.