As others noted, it is almost impossible to burn 1000 calories in an hour for an average individual. But I do not agree with that. Because that it is possible, since I do it once or twice per week.
To burn as many calories as possible. Most people usually suggest High Intensity (Interval) Training. But the problem with that style of training is recovery. You can not expect to do a very intense sprint, workout circuit etc. for an entire hour.
So to burn most calories, you should instead opt to do so moderate intensity for an entire hour. What I suggest is indoor cycling (spinning).
I have an indoor trainer for both my treadmill and bike. For anyone wondering, this is it:
It has a power meter – That means my calorie burn is actually measured, not just calculated. I use my road bike on it, and my sessions usually take 45 to 75 minutes, in which I burn from 750 to 1200kcal.
For example :
My last session took me 50 minutes and burned 900kcal.
Do not get me wrong. It is still very intense, but it is not HIIT. Which enables you to go hard for longer. And besides, cycling is the easiest way to push your body over the limits in your head.
Is it dangerous to burn 1000 calories on a treadmill?
Yes, walking on a treadmill always has some danger. But 1,000 calories is easily achievable if you work up to it. Walk on a good quality machine with a resilient deck made for running. Then listen to your body, and use common sense.
To burn 1,000 calories requires walking roughly 10 miles. Walking on a treadmill is somehow less dangerous than hiking in the woods. But even so, you would need something like three months of continuous conditioning. In order to get safely up to that level.
But there’s also something else you need. Shoes. Lots of different kinds of shoes—preferably including :hiking boots, running shoes, and some of the better made toe shoes (and socks). Why? Treadmills are flat. Every step is nearly identical to every other. You don’t just get blisters and calluses. Check out the best treadmills.
How it works on a treadmill.
You get a very specific type of callus from your toes rubbing each other in exactly the same spot on every step. The best solution I have found is to switch to toe shoes about two days out of every week.
But unfortunately, very few toe shoes have the cushioning and support (arch and ankle) needed for safe endurance walking, so it’s a trade off. 1000 calories can be burned easily.
When I first set up my treadmill desk, I lost 45 pounds in six months. Then I hurt a tendon in my ankle and had to quit for 6 months. When I checked my records, I found that some days I had walked 20 miles.
Unless you are 20 years old and in the army, don’t do that. And when my wife was in the army. A girl in her platoon snapped the ball off the end of her femur stepping down off the bus after a 20 mile hike with full pack.
You can get seriously hurt, just walking, and treadmills account for a disproportionate number of home injuries. So use your noggin.
Aside from conditioning, proper footwear, and listening when your body says, “enough,”. Make sure there is nothing behind the tread that will hurt you if you fall on it. Believe it or not, that is by far the number one source of serious treadmill injuries.