Most studies demonstrated increased total ghrelin/ghrelin levels (n = 16) after aerobic [12,136,142,143,144,145,146,147,148,154], resistance training [29,150,152], combined [149,151], or intermittent training [28] among healthy normal weight [142,149,150], overweight/obese [28,136,143,144,145,146,147,151,152,154], or clinical overweight/obese with type 2 diabetes mellitus [148] or metabolic syndrome [29] and among children with precocious puberty [12]. The gene discussed is GHRL; the disease is metabolic syndrome.