HIIT Workout Effectiveness??

DAVE_K

I've started doing HIIT in the mornings. Before this it was the long slow slog of run in the morning which I thought was the most efficient way of burning calories but my body seems to have accustomed myself to it hence lessening the effect.

My HITT session at the moment is
steady run from the car to the running track (3 mins)
4 times round a 400 metre track (sprint 100, jog 100, sprint 100, jog 100) (approx 8 mns)
steady run back to the car (3 mins)
Total 12 mins. I plan on pushing this up by putting an extra circuit in on the track every few weeks.

Is this a well enough planned HIIT session for optimum effectiveness?

I do it first thing (7 am) and don't eat for an hour afterwards with the following frequency

Monday: 40 mins jog
Tuesday: HIIT
Thursday: HIIT
Friday: 40 mins jog

I'm pretty fit as it is so the body is able for the HIIT sessions.
Would I be better off doing HIIT for the four days. My motives for HIIT are keeping the paunch off and keeping the body in good cardiovascular condition?
I do a pretty quick weights session (30 - 40 mins) lunchtimes (2 pm) on the same days which is split into

Monday and Thursday: Chest, Back and Abs
Tuesday and Friday: Arms, Legs, Shoulders

So i don't know whether tailoring this to fit in with the HIIT is something i should be looking at? I've got the nutrition side of things fairly sorted, but i sit at a desk and on the M50 all day which doesn't burn many calories

HammerHeadGym

Hey Dave,
Sounds good, but try throwing in a couple af sets of push ups, sit ups, air squats, burpees and chins if poss. Say six of the hard ones and twelve of the easy ones every other lap. You'll prolly get a visit from pukie, but watch your fitness soar.

amazingemmet

I wouldn't do HIIT on an empty stomach as it mainly an anerobic exercise so most the fuel need comes from glycogen stores not fat stores and the weight loss component comes from the metabolism boost your body gets from doing this type of exercise.

On a side note i prefer to use 200m sprint, walk 200m etc

DAVE_K

try throwing in a couple af sets of push ups, sit ups, air squats, burpees and chins

Yep i'm with ya - did the like (sprawls) between rounds in MMA before and it does certainly up the tempo a bit - i'll give it a lash next session....thanks

Is this for real on the no HIIT on empty stomach thing? I've read on a few web sites that was the way it was most effective way to do it e.g. http://www.eas.com/training/hiit/index.asp
Not that the websites can't be wrong - i'm just not sure now.

quozl

I don't know if it's more or less effective with an empty stomach but the amount of glycogen you're going to use in that 12 minutes of activity is pretty small compared to the amount you'll have in your liver and muscles. Even after a nights sleep.

So either way, you won't be causing yourself problems.

amazingemmet

quozl wrote:

I don't know if it's more or less effective with an empty stomach but the amount of glycogen you're going to use in that 12 minutes of activity is pretty small compared to the amount you'll have in your liver and muscles. Even after a nights sleep.

So either way, you won't be causing yourself problems.

I'd disagree there and say that if your doing your HIIT at a high enough intensity you could deplete up to 200g of glycogenn from your stores which is a lot.

Also the way to think about sprinting type training is its the same type of muscle workout as weightlifting (similiar force output and type of contraction) so you'll need fuel for it. And the main benefits will be derived from the metabolism boost whihc your system goes under for the next 12-20 hours.

g'em

quozl wrote:

I don't know if it's more or less effective with an empty stomach but the amount of glycogen you're going to use in that 12 minutes of activity is pretty small compared to the amount you'll have in your liver and muscles. Even after a nights sleep

There are studies supporting both HIIT on an empty tummy and with food. As Emmet said HIIT is effectively like weight-lifting, would you lift heavy having not eaten for 12 or so hours? Your body will be in a catabolic state and so if you choose to do HIIT on an empty stomach at minimum make sure you get protein and simple carbs in straight afterwards.

It's an each to their own thing- personally on the few occasions I've done HIIT first thing on an empty stomach (versus a half hour after getting some protein and carbs in) it's left me exhausted and drained for the rest of the day. With food in me though I feel energised and full of beans even after intense HIIT. The food you take in beforehand won't negate your fat-loss efforts.

OP, HIIT is very, very effective, done right it will keep your metabolism revved for up to 24 hours afterwards (needless to say those 100m sprints should be done at maximal effort), so see how you go with the couple of sessions a week and progress from there. Of course to really keep the paunch at bay increase the resistance training- increased lean muscle mass will cause your meatbolic rate to be elevated all the time.

quozl

amazingemmet wrote:

I'd disagree there and say that if your doing your HIIT at a high enough intensity you could deplete up to 200g of glycogenn from your stores which is a lot.

Also the way to think about sprinting type training is its the same type of muscle workout as weightlifting (similiar force output and type of contraction) so you'll need fuel for it. And the main benefits will be derived from the metabolism boost whihc your system goes under for the next 12-20 hours.

That seems a bit strange to me but you could be right. However your muscles and liver will store up to 2000 calories of glycogen. I've also read that you'll only lose about 300 or so over-night - that's the figure I see given as the number of calories you need to replace the morning of a marathon to make up for the calories lost over-night.

So even if somehow you'd only 1200 calories of glycogen left in your muscles and liver, how could you come close to using that in a 12 minute HIIT session?

Then after the session you have that nice post-exercise window to get some carbs into you and have it rapidly taken up by your muscles.

amazingemmet

Well at 4cals per g of carbs if your training at a high enough intesity then you could use 800cals in those few mins and the taper down to normal heart rate. Completely depends on the intensity of course though. Plus chances are your gonna be catabolic from the sleep without eating before the training session your cortisol levels will be through the roof by the end of it.

DAVE_K

Plus chances are your gonna be catabolic from the sleep without eating before the training session your cortisol levels will be through the roof by the end of it.

Say what??