"You are probably just gaining muscle"

Can you gain strength without building muscle? I consistently do better in my strength workouts on a calorie deficit :P

Absolutely. 99% of strength gains have nothing to do with building more muscle tissue. Strength is all about neuromuscular adaptation, which is a fancy way of saying, "training your brain to use your muscle." Most average people only use about 10-20% of their actual muscle tissue for day to day activities. The rest of it is just there, doing nothing. When you start serious weight training, your brain realizes it needs to use more than the normal, so for example, you squat. Essentially a squat is the same motion as sitting down in a chair and standing up. Your brain is used to that. Add a bunch of weight to the squat, and remove the chair, and suddenly you're doing a lot more work. Your brain says "whoa!" can't get buy on the little bit of muscle you've been using. So it gets to work, creating new nerves to control more of the muscle fibers. As your brain activates more muscle tissue, you get stronger.

Because when you train your muscles are under stress and they develop little tears. It's just how they deal with the stress of you doing stuff to your body. They then flood with water to repair and protect themselves. Drinking lots of water helps with this as it flushes through the stuff and stops your body hoarding the water so much.

I was going to say the exact same thing. Muscle building (at least a physical noticable difference) usually takes about 6-7 weeks to set in, which usually results in about the 1-2lbs a month a previous poster was talking about. I don't necessairly agree that you can't build muscle if you're in calorie deficit. I eat in calorie deficit, but lift 2x a week and have been developing muscle. I'm trying to lose weight as well, as build muscle. It's REALLY all about eating the RIGHT kind of macros (carbs, protein, fat) vs eating a certain amount of calories.

Absolutely not true. Total calories are the most important factor in gaining or losing. The body needs X amount of calories to sustain itself, and if you are in deficit then all of the calories you do eat are being used just to sustain bodily function, with stored fat making up the difference. The body is not going to add new tissue when it can't support the current amount of tissue it has, it's basic physics, biology, and even logic. You can't repair a building and make it taller if someone doesn't give you enough material to maintain it, the body works the same way.

Because when you train your muscles are under stress and they develop little tears. It's just how they deal with the stress of you doing stuff to your body. They then flood with water to repair and protect themselves. Drinking lots of water helps with this as it flushes through the stuff and stops your body hoarding the water so much.

I was going to say the exact same thing. Muscle building (at least a physical noticable difference) usually takes about 6-7 weeks to set in, which usually results in about the 1-2lbs a month a previous poster was talking about. I don't necessairly agree that you can't build muscle if you're in calorie deficit. I eat in calorie deficit, but lift 2x a week and have been developing muscle. I'm trying to lose weight as well, as build muscle. It's REALLY all about eating the RIGHT kind of macros (carbs, protein, fat) vs eating a certain amount of calories.

Absolutely not true. Total calories are the most important factor in gaining or losing. The body needs X amount of calories to sustain itself, and if you are in deficit then all of the calories you do eat are being used just to sustain bodily function, with stored fat making up the difference. The body is not going to add new tissue when it can't support the current amount of tissue it has, it's basic physics, biology, and even logic. You can't repair a building and make it taller if someone doesn't give you enough material to maintain it, the body works the same way.

^^This response should be stickied!

It is possible to gain muscle whilst on a calorie deficit but only in limited circumstances: overfat beginners, those new to training, formerly athletic people coming back to training after a layoff. However, the amount is limited and a short term phenomenon only (although I have seen a study which challenges this notion but it was too limited in scope to draw solid conclusions from).

The confusion arises because people use the terms lean body mass (LBM / fat free mass) which includes water and muscle mass interchangeably. Therefore when people say it was an increase in muscle they probably mean water / fluid stored to help with muscle repair or due to inflammation.

I think people tend to ask the wrong type of questions in this regard. It is far better to ask yourself "am I getting stronger" "do I feel better" or "do I look better". If the answer is yes then obviously: keep doing what you are doing and let the scale worry about itself....

THANK you for that last paragraph!!! I was having this discussion with my mom yesterday. In HER opinion, if the scales are not going down or not fast enough, then you are not being successful EVEN though in the NEXT breath she said she could tell I was getting smaller!!! I tried to tell her it's a COMBINATION of scales and measurements! I would say after almost 70 lbs total lost and over 6 inches in hips and waist EACH (not combined) I've been VERY successful! I try not to let her opinion derail me. Sometimes it's hard, but just after we talked yesterday I went to town and EVERYONE I saw who knows me was like WOW!!!!

Really, the scale is pretty much the worst measurement of fitness. It's also the easiest, and therefore it's hard not to fall into the trap of thinking you're not improving if your weight isn't going down at a certain regular pace.

A much better way to judge your fitness is what you describe above - how do you fee? How are your clothes fitting? What do people spontaneously say about how you look? With a little more effort, you could take your own measurements - but don't go overboard on this, either.

Even though you won't gain muscle size, your muscles will get stronger during the recovery process, so you'll notice improvements in the weights you can move - and be sure to keep trying to add weight to your routines regularly (it does not have to be every week, but be sure you're moving weights that are challenging for you... if you finish a set, and think to yourself, 'Wow, tha'ts never been that easy before - I made it to 10 reps without a big problem" then it's definitely time to add weight.

I have to tell you, if I could look and perform like Tony Horton, I'd be fine if I weighed 400 pounds.

A quick note on recovery: I just took a recovery week last week (week 4 of P90-X), and when I started up again yesterday, I was in much better shape. Recovery is critically important: plenty of rest, plenty of water, and keep up with the protein. (I also did drop 2lb, but some of that was probably muscle mass, too - it's a drag but it's part of the process)