An interaction between obesity, impaired glucose metabolism and sperm function in adults has been observed but it is not known whether exposure to a diet high in fat during the peri-pubertal period can have longstanding programmed effects on reproductive function and gonadal structure. This study examined metabolic and reproductive function in obese rats programmed by exposure to a high fat (HF) diet during adolescence. The effect of physical training (Ex) in ameliorating this phenotype was also assessed. Thirty-day-old male Wistar rats were fed a HF diet (35% lard w/w) for 30 days then subsequently fed a normal fat diet (NF) for a 40-day recovery period. Control animals were fed a NF diet throughout life. At 70 days of life, animals started a low frequency moderate exercise training that lasted 30 days. Control animals remained sedentary (Se). At 100 days of life, biometric, metabolic and reproductive parameters were evaluated. Animals exposed to HF diet showed greater body weight, glucose intolerance, increased fat tissue deposition, reduced VO2max and reduced energy expenditure. Consumption of the HF diet led to an increase in the number of abnormal seminiferous tubule and a reduction in seminiferous epithelium height and seminiferous tubular diameter, which was reversed by moderate exercise. Compared with the NF-Se group, a high fat diet decreased the number of seminiferous tubules in stages VII-VIII and the NF-Ex group showed an increase in stages XI-XIII. HF-Se and NF-Ex animals showed a decreased number of spermatozoa in the cauda epididymis compared with animals from the NF-Se group. Animals exposed to both treatments (HF and Ex) were similar to all the other groups, thus these alterations induced by HF or Ex alone were partially prevented. Physical training reduced fat pad deposition and restored altered reproductive parameters. HF diet consumption during the peri-pubertal period induces long-term changes on metabolism and the reproductive system, but moderate and low frequency physical training is able to recover adipose tissue deposition and reproductive system alterations induced by high fat diet. This study highlights the importance of a balanced diet and continued physical activity during adolescence, with regard to metabolic and reproductive health.

Maternal protein malnutrition during the last third of pregnancy malprograms the metabolism of rat offspring, resulting in increased vulnerability to HFD-induced obesity, and the correlated metabolic impairment might be associated with lower sympathetic nerve activity in adulthood.

Key pointsr Cancer growth, cell proliferation and cachexia index can be attenuated by the beneficial programming effect of moderate exercise training, especially if it begins in adolescence.r Walker 256 tumour-bearing rats who started exercise training during adolescence did not revert the basal low glycaemia and insulinaemia observed before tumour cell inoculation.r The moderate exercise training improved glucose tolerance and peripheral insulin sensitivity only in rats exercised early in adolescence.r The chronic effects of our exercise protocol are be beneficial to prevent cancer cachexia and hold clear potential as a nonpharmacological therapy of insulin sensitization.Veridiana Mota Moreira has worked in higher education as an effective member of a research ethics committee, a co-ordinator of physical activity and health research laboratories, an editor and reviewer in major scientific journals, a professor in Physical Education, and in Nursing, Biology and Physiotherapy Degree Courses. She has supervised and co-ordinated monographs and internships in Physical Education. She has participated in a high-performance soccer team as a physiologist. She participates in the Developmental Origins of Health and Disease (DOHaD) research group at the Laboratory of Cellular Biology of Secretion co-ordinated by Paulo Cezar de Freitas Mathias. In the future, she intends to study the application of molecular biology techniques associated with cancer, aiming to understand the multiplicity of cellular networks involved in the response to physical training, providing mechanisms by which the muscular system communicates with other organs, and mediating the beneficial effects of physical exercise related to health at different ages. * These authors contributed equally to this work. AbstractWe tested the hypothesis that moderate exercise training, performed early, starting during adolescence or later in life during adulthood, can inhibit tumour cell growth as a result of changes in biometric and metabolic markers. Male rats that were 30 and 70 days old performed a treadmill running protocol over 8 weeks for 3 days week -1 , 44 min day -1 and at 55-65%V O 2 max . After the end of training, a batch of rats was inoculated with Walker 256 carcinoma cells. At 15 days after carcinoma cell inoculation, the tumour was weighed and certain metabolic parameters were evaluated. The data demonstrated that physical performance was better in rats that started exercise training during adolescence according to the final workload andV O 2 max . Early or later moderate exercise training decreased the cachexia index, cell proliferation and tumour growth; however, the effects were more pronounced in rats that exercised during adolescence. Low glycaemia, insulinaemia and tissue insulin sensitivity was not reverted in Walker 256 tumour-bearing rats who trained during adolescence. Cancer growth can be attenuated by the beneficial programming effect of moderate exercise training, especially if it begins during adolescence. In addition, improvement in glu...