My son is 6'3" about 235, 16% body fat - age 17.

Goals - improve strength, maintain weight or loose up to 10 lbs, decrease body fat

During off-season conditioning, how many calories does he need? What percentages of protein, fat and carbs?

He does not eat fast food or soda. Eats whole grain carbs, lean meat and organic fruits and vegies and lots of water.

thanks....

I believe you need 1 gram of protein per body pound. So he'd need about 235 grams of protein per day. Nutrionists say that protein calories should be about 15-20% of total calorie intake. Carbs should be 60-70% and fats make up the rest, 15-20% as well. Hope that helps.

I would agree with 3000 on his percentages of protein,carbs and fats. I disagree with his calculations on protein to body weight. The correct quantity is 1.2 to 1.4 g of protein per kg of body weight. If your son was an endurance athlete then aim for the higher quantity for baseball use the lower quantity of 1.2 g per kg of body weight. A kg is a little more than 2.2 lbs. If you calculate his needs for quality protein it would be closer to 128 g daily.
Your sons current body fat is in the normal range for the general populace. If you want to lower body fat you can use the following formula:
Present BW (235) x present BF% (.16)=fat weight 37.6 lbs
present BW(235) -FW(37.6 lbs)= fat free weight(197.4)
FFW/desired weight% of fat free mass(197.4)/.87=226.8 lbs
Present body weight(235)-goal weight(227)=8 lbs
This is based on your information of 235 current weight and body fat % of .16. The goal was a loss of 10 lbs. This calculation provides 8 pounds lost and a body fat % of .13.
To figure kcal(calorie) to burn fat and preserve muscle use 35 to 38 cal per kg(2.2 lbs of body weight) or 35x108=3780 cal per day during his off season program. The 108 was derived by dividing 235/2.2lbs. The percentages given by MR3000 earlier are a good index to start with.
Sorry for the length of this but I do not think answers concerning a young athletes health can be given in short answer form. This is only a relatively short overview but hopefully it is a place to start. Best of luck in your son's activiies.

Thanks for your replies. I will try to figure out the protein needs in lbs and see just how much grilled chicken I need to cook every day!

During the offseason your son needs 3,910 calories. During the Postseason he needs about 3,220 calories, In season, if he is a starter he needs about 5,290 calories, and if he is a non starter he needs about 4,600 calories.

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