The aim of the research was to design a training program using cross-training during the transitional period and to know its effect on some physical abilities (muscular strength of the two men, muscular strength of the two men, muscular strength of the back, transitional velocity, trunk and thigh elasticity, agility, musculoskeletal, physiological, (Long-tertiary-high) under (18) years. The researcher used the experimental method on a sample of (12) players for the long, thirtieth and high jump in the eastern region And a research tool: physical tests - physiological measurements - cross-training program during the transition period. The most important results are: 1. The proposed cross-training program during the transition led to maintaining the level of physical abilities (muscular strength of the two men - muscular strength of the two men - muscular strength of the back - transitional velocity - trunk and thigh elasticity - agility - muscle strength of the arms) for jumpers (long, triple, high) Under (18) years. 2. The proposed cross-training program during the transitional period led to the maintenance of the physiological variables (heart rate, systolic blood pressure, diastolic, biological capacity, self-mute time, oxygen consumption index) for jump athletes (long, triple, high) Under (18) years