The purpose of this work was to describe changes in metabolic activity in the bones of young male competitive cyclists (CYC) as compared with age-matched controls (CON) over a one-year period of study. Eight adolescent male cyclists aged between fourteen and twenty, and eight age-matched controls participated in this longitudinal study. Serum osteocalcin (OC), amino-terminal propeptide of type I procollagen (PINP), beta-isomerized C-telopeptides (β-CTx) and plasma 25 hydroxyvitamin D [25(OH)D], were investigated by an electrogenerated chemiluminescence immunoassay. Analysis of variance revealed no significant differences in formation and resorption markers between cyclists and controls. Within the groups, both CYC and CON showed decreased OC at −30% and −24%, respectively, and PINP where the figures were −28% and −30% respectively (all p < 0.05). However, only the CYC group showed a decrease in [25(OH)D], lower by 11% (p < 0.05). The similarity in the concentrations of markers in cyclists and controls seems to indicate that cycling does not modify the process of bone remodeling. The decrease in vitamin D in cyclists might be detrimental to their future bone health.

The present results support the idea that cycling during adolescence may be associated to a decrease in bone turnover that may affect bone health later in life.

Teachers' perception of insufficient training is one of the reasons why outdoor activities are not carried out properly in some schools. The aim of this qualitative study was to know the opinion of future teachers about this content. A total of 62 students (34 men and 28 women; 22.74±1.57 years) from the Degree in Primary School Education from a Spanish university participated voluntarily. To collect data, practice diaries were employed, completed at the end of the different work contents. A content analysis of the 477 journals delivered through the software NVivo 12-Plus programme was carried out. Previously, a category system defined by two dimensions was established: Firstly, the sensations aroused by the practice of outdoor activities; secondly, their possible replicability in a Primary School classroom. In the first dimension, references to the emotional and social facets dominated. In the second one, the perception of an improvement in professional performance and the intention of replicating it due to its high educational value, as well as the limitations to its applicability in schools were remarkable. It can be concluded that initial training should focus more on finding solutions to the limitations encountered by students.