The physical preparation of the elite athlete results from a complex and very demanding daily training. In this process high energy expenditure (EE) occur compensated by a proportional energy intake, thus contributing to neutral energy balance and weight maintenance. However, a positive energy balance (and consequently an increase in weight) is expected after the end of the sports career if the energy intake is maintained for lower EE. While clinicians and researchers are concerned with the average individual whose physical activity (PA) level is far below the recommended exercise dose an often overlooked group are the former highly competitive athletes, who have been exposed to higher amounts of vigorous PA during times of training and competition.

It is common that upon retirement energy intake does not match the dramatic decrease in overall energy expenditure leading to a positive energy balance, and consequently weight gain. The change to a lower physical activity level does not induce an equivalent reduction in energy intake. Varying physical activity level from 1.8 to 1.4 over 7 days was not associated with a change of energy intake and there was no tendency for energy intake to drop as the sedentariness progressed.

In fact, elite athletes that became inactive are susceptible to various chronic diseases such as obesity, diabetes and cardiovascular disease. Not only obesity and its comorbidities are a major health problem as an increase in body weight and a higher risk for developing hypertension, type II diabetes and cardiovascular disease has been observed in athletes that retired from the sports career . However, the literature reports that this risk is only present in those retired athletes exposed to a sedentary lifestyle. In fact, the current levels of PA are more protective against the development of cardiovascular disease in former athletes than their past sports history. Although it is expected that the retired elite athlete will be engaged in regular PA throughout life, studies reveal that this assumption does not apply to all former athletes. This concern was addressed in the United States, namely within the National Football League where an obesity prevention program for the retired athletes was implemented. In Portugal \~50% of the former elite athletes are overweight/obese and \~30% are inactive, based on self-reports measures. Indeed no support is provided for maintaining a healthy lifestyle after the end of the sports career. If a healthy lifestyle promotion among post-career elite athletes would contribute to avoid the observed rates of overweight/obesity it is unknown. Considering this actual context, the aim of this research project is to analyze the effect of a lifestyle intervention in former athletes. To accomplish the goals the investigators will perform a 1 year randomized controlled trial with a 4-month lifestyle intervention and an 8-month follow-up in 100 volunteered former overweight (Body Mass index\>25 kg.m-2), inactive elite athletes that represented Portugal in international competitions during 1972-2012, ended their career for at least 2 years prior the study and are able to attend the educational sessions. Participants will be randomly assigned into 2 groups: i) dietary counseling (control group), or ii) behavioral lifestyle intervention, focusing on diet and PA. All participants will be screened at baseline, 4 months, and 12 months. A broad set of parameters will be assayed in each participant, namely: body composition, cardiorespiratory fitness, muscle strength, biochemical parameters, resting metabolic rate, nutritional intake, daily PA, and quality of life. These variables will allow the comprehension of the effects of a lifestyle modification on fatness, fitness and health-related parameters contributing also to further elucidate compensatory mechanisms associated with potential changes in weight and composition. To accomplish the main goal the research team will use established methods in the literature as well as novel procedures, which will enable the research team to overcome some of the limitations of previous studies. At the end of the study the investigators expect to have collected consistent data about whether a lifestyle intervention is or is not able to effectively decrease fatness while improving fitness and health-related markers. The research team believe that these data will help both non-governmental and governmental stakeholders in sports and education to make evidence based decisions, specifically the introduction and implementation of lifestyle programs in the transition to the post-career of elite athletes. The growing number of elite athletes supported by the government along with the recent EU report guidelines on dual careers in high-performance sports (ec.europa.eu/sport/news/2013/20130123-eu-guidelines-dualcareers_en.htm) requires further studies that test the role of preventive and educational programs for athletes in the areas of healthy living. The past experience of the research team in body composition, physical fitness, and objectively measured PA using cross-sectional and prospective study designs in athletic and non-athletic populations, as well as in the conduction of PA intervention clinical trials, together with the involvement of the Portuguese Olympic Committee as partners, supports the chances of successfully achieving the proposed objectives.