title: Seasonal variation of cardiorespiratory fitness of grain farmers.
mesh_terms: D000328:Adult; D000368:Aged; D000383:Agriculture; D001835:Body Weight; D002170:Canada; D002245:Carbon Dioxide / Q000378:metabolism; D002523:Edible Grain; D005080:Exercise Test; D006321:Heart / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D010809:Physical Fitness; D012119:Respiration; D012143:Respiratory Physiological Phenomena; D012621:Seasons; D012885:Skinfold Thickness; D013147:Spirometry; D013177:Sports
chemical_list: D002245:Carbon Dioxide