I always tell myself im going to stay on the treadmill for an hour, or bike for an hour. But after 30 min. I usually end up giving in. Does it make a difference if you can only do 30 min intervals, 2-3 times a day. Other than just doing it all at once?

30 mins is a totally respectable increment of exercise and it's fine to do 30 mins twice a day. If you would find it more convenient to do one longer exercise session a day, why not try to work slowly towards a 60 minute session: 30 mins today, 35 tomorrow, 40 next week and etc. Fitness is something to build up to.

But there's nothing wrong with working out in 30 minute increments (except that it means lots of extra showers!)

I think two 30 minute sessions is a great idea! The point is, you are doing it! You can build up to an hour if you want to - but the calorie burn is there either way.

I am of the mind of "whatever works for you" I tend to do to the gym, when my kids are in school and then later I take the dog out for a walk. It all counts. I like the walking because I get to listen to my audiobooks

According to Bob Greene, exercising in smaller increments multiple times each day is actually beneficial because each time you exercise it boosts your metabolism. He recommends doing a minimum of 10 minutes in each session but 15 or 20 is better.

My goal for TBL Watch Me Bloom challenge is to break up my workouts into 2 sessions Mon - Fri to keep my metabolism up as high as I can. Minimum of 20 minutes each session.

Best of luck to you!!!

I have heard that it takes 15 minutes of excercise for your body to start burning fat, but I think that any exercise is better than none. I think it works better for me to make my own rules as long as I am working out consistently and eating healthy.

I actually read an article in M&F Hers that when you work out for 30 mins, take a 20 min break and then workout for another 30 mins you dramatically raise levels of the hormone that regulates metabolism and fat-burning, compared with individuals who workout for 60 minutes straight. Since I only have an hour in the morning, not sure I can take advantage of this information, but it is food for thought...

Meta, if you have an hour, you could try doing 15 minutes of cardio to get your heart rate elevated, then lift weights for half an hour with minimal rests to keep your HR up, and then finish off with another 15 minutes of cardio. I like this myself because it breaks up the cardio boredom and really maximizes calories burned by keeping my HR high throughout the entire hour.