IJCS | Volume 31, Nº3, May/ June 2018

210 Different sports and training methods result in varied cardiac remodeling patterns. A predominantly eccentric hypertrophy is expected to be found in a marathon runner, whereas concentric hypertrophy is expected in a weightlifter. 6 However, most of the sports practiced nowadays are influenced by the two components of the exercise (the dynamic and the static), and the adaptation these athletes may undergo is less predictable. The intensity, duration and frequency of physical exercise are characteristics that can determine different patterns of cardiac remodeling. High-intensity training is associated with more marked structural and functional changes. 7,8 The aimof this studywas to verify if there is additional cardiac remodeling in athletes of competitive level, when exposed to a high-intensity training protocol performed in a military course of special operations troops. Methods This was an observational and prospective study, which evaluatedmilitary personnel at the beginning and end of a course directed at special operations troops. The selected military personnel were candidates to complete the special operations troops course, the PortugueseArmy Command ( Comando do Exército Português ). There were 76 candidates, of which 45 were previously athletes who competed in different modalities. Only 17 individuals successfully completed the course, all of them athletes. The evaluations were carried out between January and June 2016. In these evaluations, carried out at 6 months intervals, a complete clinical history including a medical questionnaire, physical examination, anthropometric evaluation and transthoracic echocardiogram (TTE) was performed. The evaluations were preceded by a rest interval of at least 12 hours. An electrocardiogram (ECG) was also performed in all participants as a cardiovascular screening method. All subjects signed the Free and Informed Consent Form prior to participating in the study. The study protocol was authorized by the Ethics Committee of Faculdade de Medicina da Universidade de Coimbra (protocol reference 087/2015). Characteristics of the study population All military men who completed the course were previously considered competitive athletes. They practiced competitive physical exercises (> 10 hours a week), participating in regional and national competitions. Although this activity was not their main economic means of support, they all had benefits derived from their sports performance. The athletes maintained their level of physical performance in the different modalities until the first evaluation carried out by the researchers. The practiced modalities can be seen in Table 1. During the special operations course, they suspended the previous training, and the physical exercise performed by them was only the result of the training given in the military course. Characteristics of military physical training in the special operations course The special operations course consisted of one component of overall physical training and another of military physical training. In the overall physical training, themilitarywas submitted to dynamic and static physical exercises, practicing several modalities such as athletics, team sports (soccer or basketball), swimming and combat sports (boxing, for instance). The military physical training combined the physical education aspect adjusted tomilitary specificities. For this purpose, themilitary performed dynamic exercises (long- distance running, long runs interspersed with sprinting andmarching exercises), static (cargo transportation and weight lifting) and mixed exercises (steeplechase track, among other activities). The special operations training program was carried out in two phases. The first one lasted 10 weeks, and the military were submitted to high-intensity exercise training, seeking to achieve approximately 77 to 95% of the maximal heart rate (HR), 9 with a frequency of five times a week and for an average of 4 hours daily, combining different types of exercise. The second phase lasted 15 weeks and included high-intensity exercises (approximately 77 to 95% of maximal HR), with periods of almost maximal or maximal intensity (> 96% of maximal HR), 9 five times aweek, for an average of 4 hours a day, alternating different types of exercise. Clinical evaluation All participants underwent a clinical history and physical examination, including the analysis of cardiovascular risk factors (CVRF), pharmacological and dietary habits, hours of training during the military course and sports history. Dinis et al. Cardiac Remodeling Induced by MilitaryTraining International Journal of Cardiovascular Sciences. 2018;31(3)209-217 Original Article