I'm currently 172 lbs, 5'8", ~32" waist, and am trying to lose weight via losing fat, and have been trying to figure out a good amount to eat per day. My exercise per day is... hard to say exactly. I'm about 6 weeks into the Insanity Max 30 Program, take a 1-hour martial arts class twice a week, go to the gym at least once a week, and do other exercises on days I'm not doing anything else. For a while, I'd been eating around 1100-1650 calories each day, but I noticed that one week, even though I eat a lot on Thanksgiving(which was in that week), I'd lost 7 lbs! I'm not sure how that's possible, but that's what the scale said.

My personal trainer suggested I should be eating 2900 - 3200 calories each day. That seems like an awful lot, doesn't it? Since he suggested this I've been eating probably around 2500 per day, and honestly think I may have started gaining weight again, but I haven't weighed myself yet. Is it even possible to lose weight eating that much each day?

tl;dr: 172 lbs, 5'8", male, aiming to lose fat, personal trainer said I should eat 2900-3200 calories per day, can I lose fat doing so?

2 Answers 2


First and foremost, I'd like to remind you that fat and weight are not synonymous, but they are related. It is possible to gain weight and lose fat, but it is also difficult.

I'm missing critical detail about your trainer, such as who he has trained and the effect he has had on those clients. If your trainer is a reputable person who is specifying your diet and training regimen, I highly recommend you just go with the program. If it needs adjusting they will adjust it on the fly. If not, then you may be right to have concerns.

Second, understand your TDEE (Total Daily Energy Expenditure). This is the amount of energy required to sustain your body's natural processes and your activities. Eating above your TDEE will cause you to gain mass, and eating below your TDEE will cause you to lose mass. Also remember that mass includes both muscle and fat.

Lastly, understand that your exercise regimen dictates just how much of your mass changes affect your fat. This is where the rubber meets the road so to speak.

  • If you are eating well above your TDEE, you will gain fat along with muscle no matter how much you exercise
  • If you are eating well below your TDEE, you will lost muscle along with fat no matter how much you exercise
  • When seeking to change your body composition, eating slightly above or below TDEE is the best approach in order to preserve or build muscle while burning fat.

The problem is that TDEE is nearly impossible to be 100% accurate with. You'll find that the amount of energy needed to maintain a certain mass is a lot more than you expect. The calculators you may find online are reasonably useful to help you get in the ballpark. After that you have to take consistent measurements to determine the effect the changes in diet are making to your body.

  • Routinely weigh yourself at the same time of day. Keep your weight in a spreadsheet or app, and average your weight for the week. This gives a more consistent view of your weight changes over time while accounting for daily fluctuations in water weight.
  • Routinely measure yourself with a tape measure to make sure your body composition is changing the way you want. If your weight isn't changing the way you want it to, then this can give you an indication of what it is you are gaining.
  • Re-educate yourself. If your clothes are fitting better and you like what you see in the mirror, and the scale is telling you that you are gaining weight, then chances are you may have less fat and a bit more muscle.

Finally, just a note that one day of eating a lot of calories or fasting isn't going to make a permanent change to your body composition. It takes several days/weeks to see any real change in body composition.

  • So would an increase in fat over muscle be indicated by greater readings on the tape measure? And if I find that I'm gaining fat or losing too much muscle, how do I correct that? Dec 4, 2015 at 17:57
  • Increase of muscle would be marked by increase in neck size size with a decrease in waist size, and/or a hip to waste ratio where the hips are more than the waste. An increase of fat would have an increase in waste size, etc and you don't fit your clothes as well. Correcting it is handled in the first three bullets. Dec 4, 2015 at 20:09
  • General rule of thumb, if you are gaining mass faster than 1 lb / 3 weeks you are probably gaining fat faster than muscle. If you are losing more than 1-2 lb / week you are losing more muscle. There are caveats, etc. but those rules of thumb are good enough to work with in most healthy adults. Dec 4, 2015 at 20:11
  • But if I'm losing weight too quickly, it probably means I am losing muscle and need to eat more, but what sort of stuff should I try to eat? It's hard to go wrong w/ veggies, but that won't ensure I have enough calories. So... proteins? Dec 5, 2015 at 1:00
  • Take a look at this article. It was helpful to me: jtsstrength.com/articles/2013/08/30/… Dec 5, 2015 at 21:36

Yes, it is possible to do so if your target is to gain muscle, but only with an intense physical regiment. With the amount of exercise that you say that you have, a good average would be around 1500-1650. A personal recommendation would be to add around 4-5 sets of 30 push ups, and around 3-4 sets of 60 sit-ups, as well as other muscle-building a day, and if you have time, to go on a 15-30 minute intense run every day. After doing this, you should raise your calorie intake to around 2000-2200 calories a day and should begin seeing effects within the month.

  • You think I should do those muscle-building exercises, in addition to the Insanity Max 30, and a 15-30 minute run? Dec 4, 2015 at 16:29

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.