Ключевые слова: 2021, adult, athlete, back, black, clothing, cold, competition, endurance, exercise, falling, field, forest, frost, jacket, jogging, male, man, marathon, men, nature, one, outdoor, pathway, people, race, real, run, runner, running, snow, snowfall, snowflake, snowy, sport, track, trail, white, winter, winter running, woodland, yellow,