My cardio class burns my muscle?

Question

I decided that I want to change my body completely, my weight is 167.5 pounds and my height is 1.65 meters. I follow a diet and I go to the gym in the night.

I have been going to the gym since two months and I lost 7.4 pounds, my routine is of 2 hours, in a hour I work with weights and in the other hour I take a class in the scaler-machine of Monday to Friday, I consider the last one like a cardio class:

• Monday: leg
• Thuesday: Back and Biceps
• Wednesday: Chest and Triceps
• Thursday: leg
• Friday: Abs
• Saturday: I take a break
• Sunday: I go out in my bicicle for a hour.

The point is that I want to burn fat, but also I want to win muscle, in the beginning this happened without problems, my muscle was increasing very good. But now I can´t see the muscle increase, I only see that my fat is going down.

Since 3 weeks ago I take the cardio class with another girl, she is very intense, to the end of the class my clothes ends completely wet, and I like it.

My question is: Does the cardio class that I take burns my muscle that I win in the first hour? Should I increase protein consumption to increase my muscle? I don't want to leave my cardio class.

Regards.

Answer 1

First of all, congratulations to your efforts and the results you are seeing so far! The plateau you perceive is not uncommon, don't let that demotivate you. Muscle gain and fat loss simultaneously is actually not impossible: Here's a discussion of two studies regarding this matter. The tl;dr points for you to take home are:

• Focus on a diet rich in proteins
• Maintain a caloric deficit above 0 and below 500 kcal.

Moderate aerobic activity (if you can perform it five consecutive days, it definitely counts as moderate in my book) does not prevent muscle growth (or even 'burn' muscles) in itself. Cardiovascular endurance training and muscular hypertrophy are two pretty different physiological processes that are not mutually exclusive as long as you provide your body with enough fuel.

Now, why can't you see your muscles increase any more? Here's my interpretation: Muscles grow very slowly. What you perceived as increase of muscle mass, was actually a process called 'neural adaption'. Basically, after just a few sessions of training, the percentage of muscle tissue you can recruit at-will increases. A lot. So if you're looking in the mirror and your biceps looks massive when flexing compared to two months ago when you weren't training yet, it's because now you're flexing 97% of the muscle instead of 60% from before (Even when not actively flexing, exercising your muscles causes an increased resting tone, adding to the 'swole' appearance). This effect plateaus quite early and your body now needs to actually build new muscle tissue ('hypertrophy') to handle the increasing training load.

So all in all, keep doing what you're doing, don't let yourself get demotivated by a perceived slow-down of progress, eat enough proteins and don't exaggerate with the calorie cutting!

Answer 2

Well, you have just left the stage of 'beginner gains'. Now is the time you will have to make a choice: build muscle or lose fat. You can't do both anymore.