Recent studies are also bringing into question the muscle loss at moderate levels of cardio.
The following is specific to endurance runners who only lost 7% muscle mass throughout a long, multi-day run and all of that was specifically in their legs. Additionally, throughout the first 2000 kms of the race (yes. 2000 km) they lost mostly fat and only turned to burning muscle in the second half of the race.
In fact, the recommended cardio of up to an hour a day is not expected to burn muscle so long as you are eating enough. It's overtraining + undereating that causes the body to burn muscle.
Which doesn't mean that strength training has no place in your workout schedule. Building muscle WILL improve your metabolism, help prevent injury, and improve your cardio workouts.
I just wish the muscle burning myth would go away.
Fitness Minutes: (2,155)
7/30/13 9:00 A
From Dragonchilde: "When you don't strength train, up to 30% of the weight loss you experience can come from lean muscle... which reduces your metabolism and raises your body fat percentage."
Nitpick -- this last part is not true. Take for instance a person who is 200 pounds and 40% body fat to begin with. That would be 80 pounds from fat. Now assume that person loses 50 pounds, 30% (15 pounds) of which comes from lean mass. That still means that 70% (35 pounds) comes from fat. The person now has 45 pounds of fat, which at 150 pounds total is only 30% body fat, a huge difference.
Here's where using your muscles while losing weight still does matter: if that same hypothetical person were able to keep it to just 10% lean mass lost, then 45 of those 50 pounds would come from fat, and at 150 pounds the person would be at only 35/150 = 23% body fat. Yet another huge difference, without having actually lost a single pound more. But it's still not accurate to say that loss of weight without strength training could ever make your body fat percentage go up. The majority of your loss is always going to come from your fat stores, assuming you have them, which most of us do.
As far as reduction in metabolism, I don't think it's fair or useful to say that lack of strength training on its own will necessarily cause any problems. I know that I personally did very little to zero strength training until quite recently, and most of my weight was lost while I was doing purely cardio. My metabolism is still quite ridiculously high to the point that at maintenance and exercising, I can barely keep up with it while eating only healthy foods, and not lose any more.
It would be more accurate, I think, to say that lack of strength training, particularly when coupled with over-cutting of calories relative to exercise intensity, is going to increase the risk that you run into metabolic problems or your body backlashing on you in other ways. (Again personally, I always kept my calories relatively high.) I think that treating it as a given just puts additional barriers in the way of people who are are trying to get healthy but have mental, physical, or other bars in the way of getting the recommended amount of muscle-building exercise. It can be done even without it. You don't always need to be perfect.
Fitness Minutes: (0)
7/30/13 4:32 A
Working out hard for 1 to 1.5 hours like you stated to me would not be a light to moderate activity level. It would be higher. That being said often people overestimate calories burned since the machines are usually incorrect. 1200 in my opinion is too low even for some sedentary people. Especially women body weight can fluctuate so I like to try to view tings in a 5 pound range.
Fitness Minutes: (41,531)
27,163 7/30/13 4:05 A
I agree with DRAGONCHILDE.
Also, you describe your Activity Level as Light-Moderate - I'm no expert but I wouldn't be having 'light' in there. By having accurate details entered in the tracker, SP works out what calorie range you need to be eating in.
Good luck, Kris
Fitness Minutes: (15,905)
9,717 7/29/13 9:46 P
1200 calories is generally not enough to support any level of exercise. It's fine for sedentary, slight women, but as much as you're burning? You need more. The weight you've put on is likely water, not muscle; that would account for the "squishy" feeling you're experiencing.
I don't think your body is hanging on to everything as fat, but it *may* be burning muscle instead of fat. Are you strength training at all? It doesn't sound like you are, since your focus is on cardio. When you don't strength train, up to 30% of the weight loss you experience can come from lean muscle... which reduces your metabolism and raises your body fat percentage.
Have you entered your information in the tracker set up here to see what range you're given?
7/29/13 9:31 P
Ok, so I'm not sure if this should go in the Exercise forum or the Nutrition forum since it is technically mix. So, if it should be redirected, just let me know and I will post it over there. :)
My current stats: Age 35 Height 5'4 Weight 145 Activity Level Light-Moderate ( I work out hard for 1-1.5 hrs etch day. The rest of the day is spent running errand, picking up the house, studying, etc)
I had RNY surgery just about 2 years ago and my maintenance caloric intake has been around 1200 for the past 8 months or so. I recently upped my workouts to everyday at a high level of effort, burning around 600-800 average workout. I have put on 5 pounds in the last 3 weeks. :( I know that people tend to retain water, put on muscle, etc when amping up a workout regime. However, my body just seems fatter. My thighs are more flabby, stomach not as flat, etc. My question is: Am i eating to little? Is my body hanging onto everything as fat? I do eat a treat everyday. I also eat oatmeal, whole grains breads, etc as carbs. I understand that some rebound is common in RNY patients. However, it seemed to happen fast and sudden. I want to avoid burning too many calories, not eating enough calories leading to storage.