Interobserver and intraobserver reliabilities of determining the ventilatory thresholds in subjects with a lower limb amputation and able-bodied subjects during a peak exercise test on the combined arm-leg (Cruiser) ergometer.

The first (VT1) and second ventilator (VT2) (anaerobic) thresholds are used to individually prescribe exercise training programs. The purpose of this research was to analyze inter- and intraobserver reliabilities of determining VT1 and VT2 in subjects with lower limb amputation (LLA) and able-bodied (AB) subjects during a peak exercise test on the arm-leg (Cruiser) ergometer. Previously published data of exercise tests on the Cruiser ergometer of subjects with LLA ( n = 17) and AB subjects ( n = 30) were analyzed twice by two observers. The VT1 and VT2 were determined based on ventilation plots. Differences in determining the VT1 and VT2 between the observers for the first and second analyses were analyzed. To quantify variation in measurement a variance component analysis was performed. Bland-Altmann plots were made, and limits of agreement were calculated. The number of observations in which thresholds could not be determined differed significantly between observers and analysis. Variation in VT1 between and within observers was small (0-1.6%) compared with the total variation, for both the subjects with an LLA and AB subjects. The reliability coefficient for VT1 was more than 0.75, and the limits of agreement were good. In conclusion, based on the results of this study on a population level, VT1 can be used to prescribe exercise training programs after an LLA. In the current study, the determination of VT2 was less reliable than VT1. More research is needed into the clinical application of VT1 and VT2 during a peak exercise test on the Cruiser ergometer.

The electrocardiographic manifestations of athlete's heart and their association with exercise exposure.

OBJECTIVE: The aim of this study was to define the minimum amount of exercise per week ('current exposure') and the total amount of exercise ('lifetime exposure') needed to lead to the electrocardiographic changes fitting athlete's heart. METHODS: All the pre-participation screenings (including electrocardiograms (ECGs)) from collegiate athletes performed at University Sports Medical Center in 2013 and 2014 were collected. Data on height, weight, sex, age, current sport(s) participation and lifetime sport(s) participation were collected. Current exposure was categorised into 0-3, 3-6, 6-10 and >10 hours/week. Lifetime sport exposure was divided into five categories: 0-1000, 1001-2000, 2001-3000, 3001-4000 and >4000 hours. RESULTS: The study population consisted of 1229 athletes (current exposure) and 1104 athletes (lifetime exposure). Current sport exposure: There was a significant increase in training-related ECG changes in the category 3-6 vs. <3 hours/week. When looking at individual parameters, we found an association with a significant difference in sinus bradycardia and QRS voltage (<3 vs. 3-6 hours/week) and first-degree AV-block (<3 vs. >10 hours/week).Lifetime sport exposure: There was an increase in training-related ECG changes that reached significance at an exposure >3000 hours. When looking at individual parameters, we found an association with a significant difference in sinus bradycardia (0-1000 vs. 2001-3000), QRS voltage (0-1000 vs. 3001-4000) and first-degree AV-block (0-1000 vs. >4000). CONCLUSION: A minimum of ≥3 hours/week of current exposure and a lifetime exposure of >3000 hours is needed to lead to the electrocardiographic changes fitting athlete's heart.

Gender differences in the electrocardiogram screening of athletes.

OBJECTIVES: Gender-related differences are frequently used in medicine. Electrocardiograms are also subject to such differences. This study evaluated gender differences in ECG parameters of young athletes, discussing the possible implications of these differences for ECG criteria used in the cardiovascular screening of young athletes. DESIGN: Observational cross-sectional study. METHODS: In 2013 and 2014 all the ECGs from the cardiovascular screenings performed at University Sports Medical Centre in Groningen of the student athletes who wanted to participate in a college sports program were collected. The ECG characteristics were scored using computer-based measurements and the Seattle ECG criteria. RESULTS: The study population included 1436 athletes, of which 72% were male. Male athletes were older (19.3 years vs. 18.6 years), participated in sports more frequently (4.0/week vs. 3.8/week) and spent more hours per week practising sports (6.4h/week vs. 5.8h/week) than female athletes. Male athletes had significantly higher PR intervals (149ms vs. 141ms), lead voltages and QRS duration (98ms vs. 88ms). Female athletes had significantly higher resting heart rates (69/min vs. 64/min) and QTc intervals (407ms vs. 400ms). Male athletes also had significantly higher amounts of sinus bradycardia (38.3% vs. 23.0%), incomplete RBBB (15.0% vs. 3.7%), early repolarisation (4.5% vs. 1.0%) and isolated QRS voltage criteria for LVH (26.3% vs. 4.6%). All P-values were ≤0.001. CONCLUSIONS: ECGs of young athletes demonstrate gender-related differences. These differences could be considered in their cardiovascular screening. For the Seattle ECG criteria we advise additional research into the clinical implications of using gender-based cut-off values for the QRS duration in the intraventricular conduction delay criterion.

Sports medicine in The Netherlands: consultation with a sports physician without referral by a general practitioner.

BACKGROUND: In The Netherlands, sports medicine physicians are involved in the care of about 8% of all sports injuries that occur each year. Some patients consult a sports physician directly, without being referred by a general practitioner. This study aims to determine how many patients consult a sports physician directly, and to explore differences in the profiles of these patients compared with those who are referred. METHODS: This was an exploratory cross-sectional study in which all new patients presenting with an injury to a regional sports medical center during September 2010 were identified. The characteristics of patients who self-referred and those who were referred by other medical professionals were compared. RESULTS: A total of 234 patients were included (mean age 33.7 years, 59.1% male). Most of the injuries occurred during soccer and running, particularly injuries of the knee and ankle. In this cohort, 39.3% of patients consulted a sports physician directly. These patients were significantly more often involved in individual sports, consulted a sports physician relatively rapidly after the onset of injury, and had received significantly less care before this new event from medical professionals compared with patients who were referred. CONCLUSION: In this study, 39.3% of patients with sports injuries consulted a sports physician directly without being referred by another medical professional. The profile of this group of patients differed from that of patients who were referred. The specific roles of general practitioners and sports physicians in medical sports care in The Netherlands needs to be defined further.