Effect of cold ambient temperature on heat flux, skin temperature, and thermal sensation at different body parts in elite biathletes.

Introduction: When exercising in the cold, optimizing thermoregulation is essential to maintain performance. However, no study has investigated thermal parameters with wearable-based measurements in a field setting among elite Nordic skiers. Therefore, this study aimed to assess the thermal response and sensation measured at different body parts during exercise in a cold environment in biathletes.

Comparison of the automatised and the optimised carbon monoxide rebreathing methods.

Recently, a new automated carbon monoxide (CO) rebreathing method (aCO) to estimate haemoglobin mass (Hb) was introduced. The aCO method uses the same CO dilution principle as the widely used optimised CO rebreathing method (oCO). The two methods differ in terms of CO administration, body position, and rebreathing time.

Body and mind? Exploring physiological and psychological factors to explain endurance performance in cycling.

Endurance athletes attribute performance not only to physiological factors, but also refer to psychological factors such as motivation. The goal of this study was to quantify the proportion of the variance in endurance performance that is explained by psychological factors in addition to the physiological factor VOmax. Twenty-five athletes of the U17 Swiss Cycling national team (7f, 18 m, 15.

Is Hemoglobin Mass at Age 16 a Predictor for National Team Membership at Age 25 in Cross-Country Skiers and Triathletes?

We recently measured the development of hemoglobin mass (Hb) in 10 Swiss national team endurance athletes between ages 16-19. Level of Hb at age 16 was an important predictor for Hb and endurance performance at age 19. The aim was to determine how many of these young athletes were still members of Swiss national teams (NT) at age 25, how many already terminated their career (TC), and whether Hb at ages 16 and 19 was different between the NT and TC group.

Influence of wheel rim width on rolling resistance and off-road speed in cross-country mountain biking.

The rim width of cross-country mountain bike wheel sets has increased in recent years, but the effect of this increase on performance remains unknown. The aim of this study was to analyse the influence of rim width on rolling resistance and off-road speed. We compared 3 tubeless wheel sets: 25 mm inner width as baseline, 30 mm width with the same tyre stiffness, and 30 mm width with the same tyre pressure.

Effect of Endurance Training on Hemoglobin Mass and V˙O2max in Male Adolescent Athletes.

Purpose: It is unknown, whether endurance training stimulates hemoglobin mass (Hbmass) and maximal oxygen uptake (V˙O2max) increases during late adolescence. Therefore, this study assessed the influence of endurance training on Hbmass, blood volume parameters, and V˙O2max in endurance athletes and control subjects from age 16 to 19 yr.

Methods: Hemoglobin mass, blood volume parameters, V˙O2max and anthropometric parameters were measured in male elite endurance athletes from age 16 to 19 yr in 6-month intervals (n = 10), as well as in age-matched male controls (n = 12).

Predicting biathlon shooting performance using machine learning.

Shooting in biathlon competitions substantially influences final rankings, but the predictability of hits and misses is unknown. The aims of the current study were A) to explore factors influencing biathlon shooting performance and B) to predict future hits and misses. We explored data from 118,300 shots from 4 seasons and trained various machine learning models before predicting 34,340 future shots (in the subsequent season).

Accuracy of Cycling Power Meters against a Mathematical Model of Treadmill Cycling.

The aim of this study was to compare the accuracy among a high number of current mobile cycling power meters used by elite and recreational cyclists against a first principle-based mathematical model of treadmill cycling. 54 power meters from 9 manufacturers used by 32 cyclists were calibrated. While the cyclist coasted downhill on a motorised treadmill, a back-pulling system was adjusted to counter the downhill force.

Reliability of the virtual elevation method to evaluate rolling resistance of different mountain bike cross-country tyres.

Although a low rolling resistance is advantageous in mountain bike cross-country racing, no studies have used the virtual elevation method to compare tyres from different manufacturers as used in international competitions so far. The aims of this study were to assess the reliability of this method, to compare the off-road rolling resistance between tyres and to calculate the influence on off-road speed. Nine 29-in.

Effect of Repeated Whole Blood Donations on Aerobic Capacity and Hemoglobin Mass in Moderately Trained Male Subjects: A Randomized Controlled Trial.

Background: The aims of the present study were to investigate the impact of three whole blood donations on endurance capacity and hematological parameters and to determine the duration to fully recover initial endurance capacity and hematological parameters after each donation.

Methods: Twenty-four moderately trained subjects were randomly divided in a donation (n = 16) and a placebo (n = 8) group. Each of the three donations was interspersed by 3 months, and the recovery of endurance capacity and hematological parameters was monitored up to 1 month after donation.

Hemoglobin Mass and Aerobic Performance at Moderate Altitude in Elite Athletes.

Fore more than a decade, the live high-train low (LHTL) approach, developed by Levine and Stray-Gundersen, has been widely used by elite endurance athletes. Originally, it was pointed out, that by living at moderate altitude, athletes should benefit from an increased red cell volume (RCV) and hemoglobin mass (Hbmass), while the training at low altitudes should prevent the disadvantage of reduced training intensity at moderate altitude. VO2max is reduced linearly by about 6-8 % per 1000 m increasing altitude in elite athletes from sea level to 3000 m, with corresponding higher relative training intensities for the same absolute work load.

Performance differences when using 26- and 29-inch-wheel bikes in Swiss National Team cross-country mountain bikers.

The purpose of this study was to analyse the effect of bike type - the 26-inch-wheel bike (26" bike) and the 29-inch-wheel bike (29" bike) - on performance in elite mountain bikers. Ten Swiss National Team athletes (seven males, three females) completed six trials with individual start on a simulated cross-country course with 35 min of active recovery between trials (three trials on a 26" bike and three trials on a 29" bike, alternate order, randomised start-bike). The course consisted of two separate sections expected to favour either the 29" bike (section A) or the 26" bike (section B).

Does hyperoxic recovery during cross-country skiing team sprints enhance performance?

Purpose: This study aimed to determine the acute responses of breathing oxygen-enriched air during the recovery periods of a simulated 3 × 3-min cross-country skiing team sprint competition at simulated low altitude.

Methods: Eight well-trained male endurance athletes performed two 3 × 3-min team sprint simulations on a double-poling ergometer at simulated altitude set at ∼ 1800 m. During the recovery periods between the 3 × 3-min sprints, all the athletes inhaled either hyperoxic (FiO2 = 1.

Does hemoglobin mass increase from age 16 to 21 and 28 in elite endurance athletes?

Purpose: It is unclear if hemoglobin mass (Hbmass) and red cell volume (RCV) increase in endurance athletes with several years of endurance training from adolescence to adulthood. The aim of this study, therefore, was to determine with a controlled cross-sectional approach whether endurance athletes at the ages of 16, 21, and 28 yr are characterized by different Hbmass, RCV, plasma volume (PV), and blood volume (BV).

Methods: BV parameters (CO rebreathing), VO(2max) and other blood, iron, training, and anthropometric parameters were measured in three endurance athlete groups AG16 (n = 14), AG21 (n = 14), and AG28 (n = 16) as well as in three age-matched control groups (<2 h endurance training per week): CG16 (n = 16), CG21 (n = 15), and CG28 (n = 16).

Live high-train low for 24 days increases hemoglobin mass and red cell volume in elite endurance athletes.

The effect of live high-train low on hemoglobin mass (Hbmass) and red cell volume (RCV) in elite endurance athletes is still controversial. We expected that Hb(mass) and RCV would increase, when using a presumably adequate hypoxic dose. An altitude group (AG) of 10 Swiss national team orienteers (5 men and 5 women) lived at 2,500 m (18 h per day) and trained at 1,800 and 1,000 m above sea level for 24 days.

Linear decrease in .VO2max and performance with increasing altitude in endurance athletes.

It has been hypothesized that one reason for decreased .VO(2max) in hypoxia could be the lower maximal exercise intensity achieved in incremental, time or distance trial tests. We hypothesized that (1).