No Evidence of a Common DNA Variant Profile Specific to World Class Endurance Athletes.

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.

ACTN3 R577X and other polymorphisms are not associated with elite endurance athlete status in the Genathlete study.

Homozygosity for a premature stop codon at amino acid position 577 in the alpha-actinin-3 (ACTN3) gene leads to α-actinin-3 deficiency. This genotype is observed in approximately 18% of Caucasians. The ACTN3 R577X polymorphism has been previously associated with indicators of physical performance in several, but not all, studies.

A common haplotype and the Pro582Ser polymorphism of the hypoxia-inducible factor-1alpha (HIF1A) gene in elite endurance athletes.

Hypoxia-inducible factor-1alpha (HIF1A) is a transcription factor regulating several genes in response to hypoxic stimuli. HIF1A target genes code for proteins involved in oxygen transport, glycolytic enzymes, and glucose transporters. We investigated whether single-nucleotide polymorphisms and haplotypes in the HIF1A gene are associated with endurance performance in the Genathlete cohort, which includes 316 Caucasian male elite endurance athletes (EEA) with a maximal oxygen uptake of 79.

Association between a beta2-adrenergic receptor polymorphism and elite endurance performance.

The Arg16Gly single nucleotide polymorphism of the human beta(2)-adrenoceptor (ADRB2) gene was evaluated in a case-control study that included 313 white male elite endurance athletes and 297 white male sedentary controls (SCs) recruited in a multicenter project from North America, Finland, and Germany. The groups were matched by country of origin. The elite endurance athletes were required to have a maximum oxygen uptake > or = 75 mL.

Effects of short-term normobaric hypoxia on haematology, muscle phenotypes and physical performance in highly trained athletes.

This study aimed to determine the impact of short-term normobaric hypoxia on physiology and performance in highly trained athletes. Twelve (7 male and 5 female) athletes were randomly assigned into two groups and spent 8 h per night for two consecutive nights a week over 3 weeks under either short-term normobaric hypoxia (simulating 3636 m altitude, inspired O2=13%) or in normobaric normoxia in a single-blind study. Following a 3 week washout period, athletes were then exposed to the other condition.

Glycogen depletion of human skeletal muscle fibers in response to high-frequency electrical stimulation.

The purpose of the present study was to evaluate the pattern of change in muscular glycogen content in response to high-frequency electrical stimulation (HFES). Muscle biopsies were taken from the vastus lateralis muscle of 7 healthy young men before, 15 min after, and 30 min after electrical stimulation delivered at a 50-Hz frequency (15 s on, 45 s off) at an intensity of 100 mA. The glycogen content of type I, IIA, and IIB muscle fibres was evaluated using microphotometry of periodic acid Schiff (PAS) stained fibres.

Treadmill and Cycle Ergometer Tests are Interchangeable to Monitor Triathletes Annual Training.

The purpose of this study was to verify the use of a single test to obtain annual training guidelines applicable to multiple modes of training. Eight triathletes (4 females, 4 males) were tested 3 times during their training year (Phase I; Phase II; Phase III) on a treadmill and cycle ergometer. Cardio-respiratory variables were calculated at standardized percentages of maximal oxygen uptake (VO2max; 50-100%).

Training profile counts for time-to-exhaustion performance.

The objective of this study was to compare the time to exhaustion (Tlim) at maximal aerobic speed (v.VO2max) in middle- and long-distance runners. Five middle-distance (MDR) and 5 long-distance (LDR) male runners, ages 28 +/- 7 years, were tested running on a treadmill, with the Université de Montréal Track Test (UMTT), on maximal velocity and on time-to-exhaustion track tests.