Ключевые слова: african, athlete, athletes, cardiology, caucasian, challenge, competition, endurance, exercise, exercising, extreme, females, fit, fitness, forest, group, healthy, hill, horizontal, international, jogging, lifestyles, man, marathon, men, motion, mountain, nature, outdoors, people, professional, race, relaxation, run, running, silhouette, sport, springtime, stamina, stretching, sun, team, trail, training, uphill, women, woodland,