If you enjoy sports as much as you love gaining, wait. If you're playing organized sports you are probably in high school, college, or fresh out of college. There will be plently of time to get fat, get past your prime, and lose control. If sports are something you like to do once a week in a beer or mens/womens league, gain weight. Ive played against so many over weight women/menin my league. If youre there to just have fun you wont mind the extra weight and you'll probably enjoy your team teasing you about your weight. So yeah depends on if you enjoy the competitiveness of sports or the kinship of sports.