I have been riding on my exercise bike for about 4 weeks now for 30 mins every day, 5 days a week and I really haven't been seeing any results.

I was wondering if there was a good interval routine I should be doing? I heard cycling 8 seconds fast, then recover for 12 seconds, and then doing that over for 20 mins.. But it tires me out to the point I can't breathe. So I was wondering if there was a better interval routine that could help me lose fat?

I have been riding on my exercise bike for about 4 weeks now for 30 mins every day, 5 days a week and I really haven't been seeing any results.

I was wondering if there was a good interval routine I should be doing? I heard cycling 8 seconds fast, then recover for 12 seconds, and then doing that over for 20 mins.. But it tires me out to the point I can't breathe. So I was wondering if there was a better interval routine that could help me lose fat?

That's the whole point of HIIT, to train you hard so that your heart becomes stronger through time, and for you to become fitter. Try cycling for 1 hour every other day and when you do HIIT the rest of the days, the 8 seconds one, increase the recovery time to 30 seconds, see if that helps a bit.

Hope this helps: UNSW: The University of New South Wales - Sydney Australia - News - How to burn more fat, with less effort

Fitfor life that's correct. You don't necessarily have to go for 20 minutes if your unable to. If you can only do 5 minutes, that's fine, but aim to do a little better each week. You could also change the resistance.

And just in note in case you didn't realise, those 12 second periods are VERY slow; as in cycle for as slow as you can so that you can put maximal effort into your next burst.

Cheers.

I've been doing 8 seconds and 20 sec rest. I did it mostly to stimulate my quads though (very heavy resistance on the work set, at the end of which speed started to slow down noticably and I had an unbarable amount of lactate) since my back is injured so squats are out.

but yeah, like the others said, do as much as you can and try to increase every week.

Good improvisation

I have to ask because I've wondered this before: are there negative side effects to making your "rest" period at too high a speed during HIIT ?

Well, the point of having real slow rests is so that you can burst maximally in the next 8 seconds that follow; you want your ATP-PC energy system to be fully replenished to do this. I'd be concerned if you were peddling too fast in the rest period because your defeating the purpose of the whole method, which has excellent and convincing results.

If I was you and it was too easy (which is what I assume), I would increase the resistance rather than peddle faster in rest. Again, you want to peddle as fast as you can in the 8 seconds as best as you can, allowing your body to release the hormones and other factors which have proven to be so successful in eliminating body fat.

Cheers.

Well it's not "easy" by any means. My intervals are way longer than 8 seconds, but that's besides the point. My sprints (either running or biking) are exhausting, but I probably don't rest as slowly or as long as most people do. Obviously you want the rest so that you can go at your best speed for the sprint portion.

I guess what I want to know is what is the science behind it, other than that it will allow for max effort in the ensuing interval? i.e. are there any physiological disadvantages ?

Thanks

Well firstly I have to say that the method has only been studied properly for exercise-bike riding. So whether the 8/12 (8 sec all out, 12 sec rest) period works for other methods such as punching, swimming, running etc is another question - although i'm sure it will be similar.

The physiological basis is that fat cells are more than just storage cells, they are highly metabolically active. From memory, I think it may even have over 20 different receptors for different hormones. The high intensity burts is what stimulate a number of hormones such as the ecatecholamines which are potent fat burners (and why continuous training is so poor at burning fat). So if your peddling too fast and aren't able to cycle as fast as you can during the intense 8 seconds then you may be interrupting your results.

I'm not specifically talking about the 8/12 method. That is just one variation of the many types of HIIT that can be done, whether it's running, biking, etc. Anyway, basically what you're saying is just that if you're not at a high enough intensity during the "intense" part, you're not maximizing the benefit. However, that is saying that it doesn't really have an actual negative effect, just not as much of a positive one. Agreed?

By the way, why would you say that continous training is poor at burning fat? Low intensity cardio burns calories mainly from fat. True, the aftereffects and resulting metabolic rate will be different, and you may end up burning less fat in the long run, but that doesn't mean that steady state cardio doesn't burn fat.

Yes we can agree.

I never said it doesn't burn fat. If you conducted a study group of overweight individuals, half doing continuous steady state, half intense workouts, the latter would lose significantly more fat. Yes, continuous exercise burns more fat in proportion, but non-steady state exercise burns similar amounts of fat in addition to other resources such as glucose; intense exercise also triggers other fat loss mechanisms which continuous state doesn't, such as releasing fat burning hormones and a number of other variables (unknown and known).

Well said. I did know this and wasn't implying that it wasn't true. I just misunderstood your point in the earlier post. Thanks for the input

Hope I helped