I hate it when my h/r goes into the 180's. I start getting light headed and woozy and it freaks me out some. Not only that, but it's incredibly difficult for me to get it that high.

When I ran 3.5 miles this morning I was in the 160's and 170's the last 15 minutes of the run. That sure doesn't seem steady rate to me. :)

I need to go in for a check up. But, I haven't worried too much about it. Honestly, if I was in perfect health at 450lbs, how I could be worse off now?

Oh dude, I know exactly what you mean about the light headed thingy. I can totally relate bro. I experienced that feeling today on the eliptical. Did 40 minutes, HR was up to 160bpm and I thought I was going pass out.

*It's always good to go...Never a bad idea just to ensure you're healthy. Thats always important. Im sure you're fine though but just to be on the safe side.

Everything I've ever heard says if you get light headed or dizzy to stop. I can admit that I haven't always stopped, but it's incredibly uncomfortable in the 180's. I was running on the treadmill one day and it was that high and when I finally slowed down I literally almost threw up right there in the gym. I've heard of it. That was my first experience with it.

Silock, what do you think of all of this? Am I just being a pussy? Where should the heart rates be for HIIT?

I think the dizziness part has to be linked to breathing.

Maybe we're going hard to the point where we overdid it for our fitness level and didn't get enough oxygen at the time. That could be very possible.

Very much so.

That's not what overtraining is. I wouldn't even be concerned about your heart rate going high. If you're around Flopnuts' age, you're in my age bracket, too. I'm 29, and I regularly get my HR over 200 (got it up to 208 a couple of weeks ago). No reason not to do that. Higher HR = better performance (up to a point) = more calories burned.

Overtraining is different than simply stressing your body. Overtraining is when you've maxed out your nervous system and it is desperately trying to raise other systems in your body to compensate for prolonged periods of increased stress. It takes a while to get into the overtrained mode, but it depends on your personal ability.

Some symptoms are:
Increased resting HR (especially when you just wake up)
Can't seem to get enough sleep
Lack of motivation
Soreness all over your body (which you'll notice is different than soreness as a result of new exercises and the body adapting to them... this one doesn't subside as quickly, but it's not as pronounced, either)
Increased oxygen consumption doing the same activity level
If you lift weights, not being able to lift as much (over a longer-term basis, not just the random fluctuations that happen to all weight-lifters)

Those are just the ones that I personally notice when I'm approaching the overtraining point, but there are others.

Good overview here:
http://sportsmedicine.about.com/od/s...inweight_3.htm

Overtraining doesn't happen overnight. It takes a while, and can generally be dealt with by taking the proper amount of rest. At least 1 rest day per week, and 1 week off of heavy weight lifting and long or intense cardio sessions every 8 weeks.

Also, just as a follow-up: You'll never be able to eliminate cortisol from your body. It's a necessary hormone and has some good effects (like an anti-inflammatory property as well as fat burning). All of the hormones in our bodies are there for a reason. The key is making sure none of them get out of their intended balance.

And cardio can be great for muscle building, as one of the side effects of a great cardiovascular system is the increased ability to deliver oxygen to muscles, which definitely helps in the weight training department.

The problem for most people is making things more complicated than they need to be. Worrying about cortisol, meal timing, cardio cannibalizing muscle tissue, etc. is stressful. The reality is that we increasingly try to compartmentalize aspects of our body into time periods. We worry about not getting enough protein within a "half-hour window after working out!" We worry about eating too many calories one day, or not enough protein that day. Our bodies aren't confined to a similar clock system. They function on a much longer time scale. As long as you're within the acceptable range over a week or a month, you'll be fine. And it greatly eases the stress of constantly worrying about whether or not you're getting the maximum benefit from your workouts and nutrition. Which leads to less cortisol :)

So, when you take a week off I'm positive you're not just sitting around the house. What do you do?

Heart rates for HIIT vary by individual. I mean, there are general theoretical maximums based on age, but the longer and harder you train, the easier it is to get your heart rate sky-high (which is a good thing, in moderation). I far exceed the theoretical maximum HR for my age, but that's because I work at it. I train on the ragged edge and constantly push myself. The heart is a muscle, too, and while it can get overtrained, it's also able to increase its function.

That being said -- light-headedness and dizzy = BAD. That could mean a number of different things, and you should definitely talk to your doctor about it. You could be in ventricular tachycardia on the treadmill, which is VERY VERY BAD.

Of course, you could also just be wussing out. Many people freak out when they start approaching their limits, because they don't train there and have no idea what it feels like. I have no idea, and I don't even want to speculate. You should take it up with your doctor.

For me, I don't light-headed when I train that high, but there's a definite difference between 180 bpm and 200. A HUGE difference. 180 is uncomfortable. I breathe very, very heavy (and I already have asthma, so that's doubly uncomfortable). I want to stop. 200 is a whole new ballgame. My entire body hurts. Breathing doesn't really happen. Every muscle strains, even if it's not being used for locomotion.

But once you learn what it feels like, you can anticipate the pain and when it will go away so you can push through it. I'm not saying that's what is happening to you, so you should definitely talk to your doctor.

Puking is also bad, but not because it's a heart-issue. That just means there's not enough blood in your guts and the body reacts by expelling whatever is in there. Bad. Good way to overtrain is to constantly train to puking.

Sit around the house. Concentrate on nutrition. Take long walks with the dog.

It's literally do nothing. Your muscles won't disappear overnight. You won't lose your ability to run. Body operates on a LOOOONG time scale. It will take months to lose what you've gained. The rest will help a lot more than doing anything will.

Whew. Every 2 months? Really?

Yeah I hear ya. I don't think our bodies are designed to operate that way. At least psychologically. I feel it ya know, when I have to think about what time of the day it is to get my meal in. It can be very stressful and painful. but I didn't think mental stress can contribute to the production of more cortisol? hmmm interesting.

About the cardio thingy and how it is good for the muscles makes me think of Biology in a sense where we lift weights lactic acid builds up in the muscle causing our muscles to feel fatigued. Glucose can be brokendown w/o oxygen but since it is a multi step process oxygen is required to break down pyruvic acid once it is produced from the breakdown of glucose, which then becomes carbon dioxide and water. Coincedentally the waste product that is excreted from the body.

Anyway, forgive me, for the rambling part about glucose. I know it has nothing to do with lactic acid, but they do say doing cardio can flush out lactic acid in the body. just thought oxygen is interesting in how it contributes and how it is needed to breakdown glucose to form both CO2 and water. That has to happen while doing cardio though

Thanks for the info. The urge to throw up happened 1 time about 3-4 weeks ago. I don't get light headed and dizzy until I get up into the 180's, but I'm not sure if it's legitimate. It hasn't happened while running at all. If I even get the inclination I'll just stop. And it happened last week. I was waxed and decided enough was enough. Long before I wanted to quit, but I figured my body just needed a rest.

That said, maybe it is time to go see the doctor for a check up and chat about what I'm doing right now. It's been too long.

Yup. It's good for you. Of course, I train very, very hard. I could never forgive myself if I just half-assed something.

I've gotten soft in the last few weeks. I mean, I spend a lot of time at it, but I'm not pushing myself every day like I used too. Now, it's just 1 or 2 days a week that I kick the shit out of myself.