I've been doing HIIT type cardio 3 times a week on my off days from lifting. I do my cardio on the eliptical and do 2mins hard and 1min light. I do a 2 minute warmup, then 20-25 mins of HIIT, followed by a cooldown. The machines have its own interval settings which are 2min low incline and resistance, 2min higher incline and resistance so I get overlapping variety.
The problem is my heartrate is reaching 180bpm which I feel is too high. When it gets up there I take an extended short intesity break until it comes down to around 160, usually twice per session.
I am not getting really winded when it reaches this high and I actually feel like I could go harder even though I'm dripping sweat by this point.
Could the machines reading just be off? I've tried multiple different machines and get the same readings. Should I not worry and eventually it will come down on its own as I condition myself better?
My main concern is burning muscle even though its a lifting off day.