Effects of the Birthplace Altitude and Training Volume on Hematological Characteristics in Youth and Junior Male Colombian Cyclists.

Purpose: The long-term development of talent in endurance sports is a topic of interest. Among various factors, the importance of total hemoglobin mass (tHbmass) and the potential benefits of being an altitude-native athlete remain unclear, particularly in young categories. This study aimed to investigate the impact of altitude and training content on hematological characteristics by comparing young male cyclists age 15-16 and 17-18 years who were born and trained at a moderate altitude (ie, greater than or equal to 2500 m; MA) and cyclists who were born and trained at low altitude (below 1000 m; LA).

Effects of a physical exercise program on HIF-1α in people with Chronic Obstructive Pulmonary Disease living at high altitude: study protocol for a clinical trial.

Background: Chronic Obstructive Pulmonary Disease (COPD) is a chronic, noncommunicable disease characterized by hypoxemia, with altered lung function, dyspnea on mild exertion, limited tolerance to physical exertion, and functional impairment. Physical exercise has been recommended worldwide as an efficient strategy to improve the autonomy and quality of life of patients affected by COPD. However, the adaptive molecular mechanisms occurring in these patients after the exposure to the hypoxic stimulus triggered by physical exercise have currently not been described in populations living at high altitude.

Effect of hypobaric hypoxia on hematological parameters related to oxygen transport, blood volume and oxygen consumption in adolescent endurance-training athletes.

Objective: To analyze the effect of altitude on hematological and cardiorespiratory variables in adolescent athletes participating in aerobic disciplines.

Methods: 21 females and 89 males participated in the study. All were adolescent elite athletes engaged in endurance sports (skating, running and cycling) belonging to two groups: permanent residents in either low altitude (LA, 966 m) or moderate altitude (MA, 2640 m).

Hemoglobin Mass, Blood Volume and VOmax of Trained and Untrained Children and Adolescents Living at Different Altitudes.

To a considerable extent, the magnitude of blood volume (BV) and hemoglobin mass (Hbmass) contribute to the maximum O-uptake (VOmax), especially in endurance-trained athletes. However, the development of Hbmass and BV and their relationships with VOmax during childhood are unknown. The aim of the present cross-sectional study was to investigate Hbmass and BV and their relationships with VOmax in children and adolescents.

Quantification of testosterone-dependent erythropoiesis during male puberty.

New Findings: What is the central question of this study? To what extent does testosterone influence haemoglobin formation during male puberty? What is the main finding and its importance? In boys, testosterone might be responsible for about 65% of the increase in haemoglobin mass during puberty. The underlying mechanisms are assumed to be twofold: (i) indirectly, mediated by the increase in lean body mass, and (ii) directly by immediate testosterone effects on erythropoiesis. Thereby, an increase in testosterone of 1 ng/ml is associated with an increase in haemoglobin mass of ∼65 g.

Influence of Endurance Training During Childhood on Total Hemoglobin Mass.

Elite endurance athletes are characterized by markedly increased hemoglobin mass (Hbmass). It has been hypothesized that this adaptation may occur as a response to training at a very young age. Therefore, the aim of this study was to monitor changes in Hbmass in children aged 8-14 years following systematic endurance training.

Efficacy of the prescription of physical activity in the obese child population.

Objective: To determine the effectiveness of prescribing physical activity to the population of overweight and obese children, in accordance with the levels of evidence.

Methods: To find literature pertaining to the intervention of physical activity in overweight and obese children. four electronic databases were used: Pubmed, Embase, Cochrane and Lilacs.

[Agreement between a fitness test and Polar S810 for estimating maximum oxygen uptake].

Objective: Identifying agreement between data for estimating maximum oxygen uptake obtained by a fitness test and the Polar S810 heart rate monitor.

Methods: This was an observational agreement study comparing two methods for estimating VO(2max) (simultaneously and independently). Two protocols were applied to 46 athletes from the Universidad Nacional de Colombia who had been trained in endurance sports (one at rest and maximum effort i).