Cardio gives you one other advantage besides the calories you burn while you're exercising and the good you're doing your heart. It's a little something fitness trainers refer to as "The Multiplier."
Based on how much activity you do, your body burns more or less calories throughout the entire rest of the day. Literally, the fit get fitter and the slow get slower. I know, it's not fair. It sounds like a way to make sure the rich get richer, the beautiful stay beautiful, and the powerful stay in power.
Well, like most rules of life, it seems unfair until you start making it work for you instead of against you.
How many more calories can you burn?
If you were to stay in bed all day long, your body would still have to do a certain amount of work to keep your blood flowing and keep you breathing and fire off a brain synapse of thought once in a while. This minimum number of calories your body burns in a day is called you "Basal Metabolic Rate," or BMR.
Based on how much activity you participate in, this number only goes up. How much?
It's 20% more even if you live in a cubicle all day and don't exercise.
If you get some exercise in a couple of times a week, or have a job that keeps you moving around a little, it's 37.5% more.
If you have a pretty strenuous job, or are doing some tougher exercise 3-5 times a week, it's 55% more.
If you're exercising hard six or seven days a week for a couple of hours, of have a job that can make you sweat every day, you can improve on your BMR by as much as 72.5%.
And if exercise is your life--you tote barges and lift bales all day, or maybe are a pro wrestler--you could burn 80-90% more than you would staying home.
All of this adds up to a couple of options, both of which are terrific. First, you could keep eating what you're eating, and increase your activity level, and that alone would be enough to slow down, stop, or reverse any weight gain you're experiencing. And, exercising combined with a more sensible diet can speed your growth phenomenally.
For example, let's say you're eating 2,500 calories a day and gaining a pound a week. If you cut back to 2,000 calories a day, the weight gain should stop (It takes 3,500 calories to make a pound of fat. 500 calories X 7 days = 3,500 calories). However, if you increased your amount of exercise from minimal to 3-5 times a week, you would actually burn an extra 583 calories a day, which means you'd also start to lose a pound week.
So tell Jack he doesn't have to worry so much about what that little counter on the gym treadmill says. First off, it's wrong, and second off, it's not so much about how many calories you burn at the gym as it is about the multiplier.
But if he wants to put out more sandwiches that are under 300 calories, that's not a problem.