In December of 2019, there was an outbreak of a severe acute respiratory syndrome caused by the Coronavirus 2 (SARS-CoV-2 or in China. The virus rapidly spread into the whole World causing an unprecedented pandemic and forcing governments to impose a global quarantine, entering an extreme unknown situation. The organizational consequences of quarantine/isolation are: absence of organized training and competition, lack of communication among athletes and coaches, inability to move freely, lack of adequate sunlight exposure, inappropriate training conditions. Based on the current scientific, we strongly recommend encouraging the athlete to reset their mindset to understand quarantine as an opportunity for development, organizing appropriate guidance, educating and encourage athletes to apply appropriate preventive behavior and hygiene measures to promote immunity and ensuring good living isolation conditions. The athlete's living space should be equipped with cardio and resistance training equipment (portable bicycle or rowing ergometer). Some forms of body mass resistance circuit-based training could promote aerobic adaptation. Sports skills training should be organized based on the athlete's needs. Personalized conditioning training should be carried out with emphasis on neuromuscular performance. Athletes should also be educated about nutrition (Vitamin D and proteins) and hydration. Strategies should be developed to control body composition. Mental fatigue should be anticipated and mental controlled. Adequate methods of recovery should be provided. Daily monitoring should be established. This is an ideal situation in which to rethink personal life, understanding the situation, that can be promoted in these difficult times that affect practically the whole world.

To compare two situations with similar magnitudes of mitochondrial substrate flux but different blood oxygen contents, one-legged training was employed. Ten healthy subjects trained one leg under normobaric conditions and the other under hypobaric conditions. At each session the subjects trained each leg for 30 min. The absolute work intensity was the same for both legs and was chosen to correspond to 65% of the average (right and left) pretraining one-legged maximal work capacity. There were three to four training sessions per week for 4 wk. Muscle biopsies from each leg were taken before and after training and analyzed for fiber types, capillaries, myoglobin, and oxidative and glycolytic enzymes. The most striking finding was a greater increase of citrate synthase activity under hypobaric conditions than under normobaric conditions. In addition, the myoglobin content increased in the leg trained under hypobaric conditions, whereas it tended to decrease in the normobarically trained leg. Because both legs were trained at the same intensity, the oxygen turnover and the substrate flux through the carboxylic acid cycle and the respiratory chain must have been of similar magnitude. Thus a difference in substrate flux is less likely to have caused the differences in enzyme activities and myoglobin content between training under normobaric and hypobaric conditions. Instead, the stimulus seems to be related to the blood oxygen content or tension.

The D allele at the angiotensin-I-converting enzyme (ACE)-insertion/deletion polymorphism has been associated with an increased risk of developing several pathological processes, such as coronary heart disease and ventricular hypertrophy. Individuals with the DD genotype show a significantly increased left-ventricular mass in response to physical training, compared to the II genotype (which would be associated with the lowest plasma ACE levels) and the ID genotype. The II genotype has been linked to a greater anabolic response. In accordance with a role for ACE in the response to rigorous physical training, a higher frequency of the I allele has been reported to exist among elite rowers and high-altitude mountaineers. Sixty elite (professional) athletes (25 cyclists, 20 long-distance runners, and 15 handball players), and 400 healthy controls were genotyped for the DNA polymorphisms of the ACE, angiotensinogen (Ang) and angiotensin receptor type 1 (AT1) genes. Plasma ACE levels showed a strong correlation with the I/D genotype in our population. The I-allele occurred at a significantly higher frequency in athletes compared to controls (P = 0.0009). Gene and genotype frequencies for the Ang and AT1 polymorphisms did not differ between athletes and controls. Since the frequency of the ACE I allele was significantly increased among our elite athletes, we conclude that the ACE polymorphism represents a genetic factor that contributes to the development of an elite athlete.

Cycling is a high intensity sport because approximately 93 min in flat and 123 min in mountain stages were above 70% of VO2max. In addition, the time spent at IAT was roughly 20 min regardless of stage type, suggesting that the anaerobic capacity limits performance.