Weight-Loss Diet vs Exercise

[DizzyEdge]

Hey there, new to the forum, and I have a (fat?) burning question that I have yet to find the answer for, so I figured perhaps someone on here could give their two cents!

Let's say your BMR is 2000 kcal, and so the general advice is to reduce that by 500 kcal to lose 1 lb per week.

What is the difference as far as effect of a) doing so by eating 1500 kcal per day, or b) eating 2000 kcal per day but doing cardio to burn 500 kcal a day?

If any?

Also, hypothetically, if you ate 2000 a day, but did crazy exercising that burned 1000 kcals a day, could you actually put yourself into starvation mode even though you're eating a normal amount?

Thanks,

 

[Steve]

Let's say your BMR is 2000 kcal, and so the general advice is to reduce that by 500 kcal to lose 1 lb per week.

That is not the general advice.

You reduce from BMR + activity. (even more things if you want to get technical)

I think you understand this concept, just mis-worded.

What is the difference as far as effect of a) doing so by eating 1500 kcal per day, or b) eating 2000 kcal per day but doing cardio to burn 500 kcal a day?

If any?

A deficit is a deficit.

Your body keeps tabs primarily on energy balance. If you're short, you're short.

However, what your deficit is comprised of can influence body composition. For instance, if while dieting part of your exercise expenditure comes from resistance training, there's a good chance you're going to look better at the end of your fat loss period than had you not lifted any weights.

But this is sort of beyond your question.

Also, hypothetically, if you ate 2000 a day, but did crazy exercising that burned 1000 kcals a day, could you actually put yourself into starvation mode even though you're eating a normal amount?

Couple of things.

The 'starvation mode' takes place regardless of the size of the deficit. No matter how small or large the deficit, you're body is going to adjust to the inadequate amounts of energy. It's just with more aggressive dieting, these adaptations can happen sooner.

Second, individual factors play a huge role in determining how quickly the above adjustments take place. For instance, someone carrying a lot of body fat generally doesn't need to worry so much about the 'starvation response' opposed to someone with much lesser body fat.

Third, you seem to be missing the fact that if you're maintenance intake is 2000 calories with regular amounts of exercise, it is no longer maintenance if you start to exercise excessively. Remember, BMR is not maintenance. BMR is what your body needs at absolute rest for things like respiration, organ function, thermoregulation, etc. Maintenance is BMR plus exercise, daily activity, food digestion, etc.

That in mind, if you're exercising like a mad man, you're no longer eating a 'normal amount' if you stick with 2000 calories.

Make sense?

 

[DizzyEdge]

Hey Steve, thanks for the info. My use of BMR for the first examples was a reflection on my previous life of being pretty sendentary

 

[Steve]

Beyond that, I hope I cleared up some of your misconceptions. If not, feel free to ask more questions.