Resistance training and HIIT

wouldn't you have better results by focusing on the compound lifts with low reps for the chest? 1-2 hours sounds really long.
lots of accessory exercises. for a cut I've reading that everyone suggests low reps heavy weight, 2 working sets.

Since your focus is lifting and any potential muscle gains, skip the HIIT.

HIIT is the answer for cardio-only people to get some benefit from a lifting type workout. Because that's exactly what it's like, lifting.

All out anaerobic effort with slight rest, repeat 8-12 times.

It's become as bad a fad as "fat-burning zone" now, both have it's place in a workout schedule, both can cause your time to be a big or small waste of time and energy spent.

But, trying to fit true HIIT in with lifting is about impossible, either you don't really do the HIIT, and it's just intervals (which is fine and has good cardio improvements), or you impact getting the most out of the lifting.

View HIIT as lifting for those muscles - would you lift with the same muscles day after day? Hopefully not.

Exercise tears down - rest is the recovery and repair and getting stronger, and eating right amount perhaps muscle gain too.

Your potential muscle increase will only come with fully loaded muscle by weight, not by time. One is a strength increase response, one is an endurance increase response.
You want strength increase.

So you want as fresh as possible muscles to handle as big a load as you possibly can. You may feel like you are pushing just as hard with tired muscles because you did HIIT the day before or worked out in the am - but it's not the same as on fresh muscles, and not the same response to repair.

If you are willing to go slow on transform, one study showed 16 weeks to drop 3.5 lbs of fat and gain 3.5 lbs of LBM (they didn't measure muscle, but likely some).

http://www.myfitnesspal.com/topics/show/778012-potential-muscle-gain-lifting-and-metabolism-improvement

That's eating at maintenance. You'll go slower if you have a deficit in there. And that is best estimate maintenance/TDEE level with deficit.

You could try to enhance that though by eating over maintenance 24 hrs post lifting, and take the deficit on the other 24 hrs. But that again means a rest.

The more cardio focused stuff is merely to increase your calories to eat - which you may want. But don't let it ruin a good lifting day.

And the Les Mill's stuff isn't heavy lifting, not enough rests from what I've seen taught through the windows. Not enough rest, can't lift as heavy.
You'll get stronger, but since more endurance based, the body's response besides strength with existing muscle will be more glucose stores to endure longer.

Cardio the day after lifting should in fact be in the "fat-burning zone", better known for many years as the Active Recovery HR zone, because you aren't, hopefully, adding more load to muscles trying to rest and repair, but just increased blood flow.

I think that will hit your desired goal much better.

ok that sounds pretty good. Well I have sports training twice a week which can be seen as Cardio I guess. Cricket. So I wouldn't mind skipping the HIIT.

Lets say I revise it to this: Would do the Lesmill pump lets say 2-3 times a week and eat maintenance on those days or just below. 2-3 times a week will do heavy. Not crazy heavy like those Hulks in the gyms but heavy enough to build lean muscle not bulk. Lets say 3-4 sets of 12-16 reps. The lesmill is complete body and then I could do the heavy for lets chest arms and back and go over maintenance on those days. Would that work? Or is that contradictory?

I'd watch the HR on the Lesmill stuff. If it gets above Recover Zone, then muscles are tired shooting the HR up. 50-59% of HRmax.

BTW, there is no such thing as building lean muscle or bulk. Endurance type muscle, but that's not really building it, but rather storing more glucose in what you got. New endurance muscle starts when you've tapped all you got already.
And then strength muscle, doing lower reps. But if not building it, it doesn't get bulky anyway.
But if you use the muscles for what they can handle, not overloading them, then there is no need to make them better - they can handle what they are being asked to do.

Well, as that study showed for men.
Newbies at lifting, so max gains there. But you've been exercising and doing sports already, so not really newbie in that sense.
You'll be strengthening the existing muscle before more is needed.
Eating at maintenance, because no weight lost or gained.
3.5 lbs of LBM (which includes but is not just muscle) in 16 weeks.

So it could take 5 months if you get max recovery and max load from the lifting.

It should take you longer then as you are doing other things.

You can shorten it up by getting max recovery from the lifting, and eating in surplus for that 24 hrs post workout. Shove most of the day's calories into the 24 hrs, or really eat extra 200.

Should have protein set to 1 gr per lb of Lean Body Mass.

So if you add a load when already sore, you aren't getting full repair, perhaps little to none depending on timing and new load. Eventually you won't be sore, but muscles are still recovering even without that, so should still be given rest or at least no additional load, just gentle use.

To emphasis the endurance aspect, but still be in the muscle growth range, 12-15 reps, 2 or 3 sets as you have time. Load appropriate to almost failure of good form on last few reps.

Interesting reading.

I do HIIT on my non-weight training days because I don't do any other heavy cardio type stuff at all, I do weights 3 x a week and walk 5 x a week. So I do the HIIT on 2 days to keep up the cardio component.

My goal is to lose a further 15kg of fat. I do weights to keep up my LBM so that when the fat does eventually go, I'll have a nice figure underneath. I don't want to necessarily gain more muscle, just keep the amount that I have. I thought that I needed to do the cardio to burn calories on my non-weight training days. And of course it's good for general fitness.

But from HeyBales comments, maybe the HIIT is pointless. Perhaps I should just do the 3 x weights and walking?

Anyway, I'd be interested to keep an eye on this thread, see what other opinions and comments pop up.