Oh sorry, I was just re-reading your first post where you said:

I thought you meant I was doing too much cardio, and I was thinking that swimming is different than regular cardio.

Yes, I'm talking about nautilus weights, I don't think I'm ready for free weights. I don't know what I'm doing, and I'd probably hurt myself. And yes that guy meant we would take turns in between sets, but I don't really wait that long in between sets. I do 3 sets of 10 reps... and then I move on. I think they can just wait their turn, it's not like I hog the machine for too long. I spend less than 5 min at each one. The only thing I spend more time on, is the back extensions because they feel sooo good. I usually do 5 sets of those, and may even come back 30 min later and do another 5 sets, and I use 70 pound weights. It doesn't feel like work, it just feels like a good stretch. If I'm doing something that works my legs/glutes, I used 50-70 pound weights. If I'm working on my arms, I use 25 pound weights. If I try much more than that, I can't make it up to 10 reps without feeling very fatigued.

The reason I can do weights and swimming, but not cardio is because my heart already beats too fast at rest. (I'm going to get all nerdy and biophysical on you...) In fact, I'm supposed to take a beta-blocker to slow it down, but it was making me too tired. So when I do any sort of sustained activity like cardio exercise, my heart beats so fast (170's) that it can't perfuse enough blood to my brain, and I faint. My cardiologist is the one who recommended aquatic exercise because the pressure of the water keeps the blood circulating... unlike being on a treadmill where it pools at your feet and has to work against gravity. It sounds worse than it actually is. I know my limits, and it's as simple as sitting down when I feel I'm going to pass out. My heart rate just doesn't increase that much while doing weights. A little, but not to the point that I am gasping for air.

AND I'm probably much stronger than I make myself sound. I have to be... to work on someone's chest doing CPR for 20 min. I'll have you know that I have successfully revived every person I've ever tried to resuscitate. Amazing what a little adrenalin can do for you!

Oh, I see. I meant proportionally less, not quantitatively less, if that makes sense. Less as a percentage of what you're doing, but not objectively less. :P

I don't want to get into an argument about this, but simply put, machines are bad. You are more likely to injure yourself long term with machines. There's no point in isolating major muscle groups if their support can't handle the weight they're dealing with. It just creates dangerous imbalances.

Sorry, but unless there are other machines of the same type available, that is a pretty objectionable level of selfishness on your part. If the dude's just trying to chat you up, then yeah, tell him to **** off, but timing and specificity of exercises are pretty important to some people, so making him wait because you can't be arsed to share strikes me as pretty inconsiderate. I can see if he's going to take 2 minutes per set or something, but if he's going to work at a similar pace, then what's the issue?

I don't ever have that problem myself, though. I have this look of animal rage on my face and make a lot of strange noises when I exercise. That tends to keep the few people who even wander over to the free weight area away from me. :P

First off, you can get as nerdy as you like. Biology is my current major. Well, that and discrete mathematics. I switch up every once in a while, but chances are I'll understand most of what you're saying.

It's funny that you should say what you have, though, because my situation is reversed. When doing moderate cardio (cycling) I cannot get my heart rate above 120 bpm (my resting rate is 50-55) for the life of me. Even 3 minutes at maximal effort (sprinting) will only get me up to about 150 bpm, which is roughly 70% for me. On the other hand, the very first set of the very first exercise I perform in my strength training workout will spike my heart rate to 170.

Okay, so that last paragraph didn't really have much to do with anything, except that what I'm getting is that you don't weight train very intensely, but for good reasons. So, yeah. That's fine. But I'd still get away from the machines. It's not that hard to learn simple bodyweight exercises. You can add weight (via a weighted vest or something) or modify positions to increase difficulty. Or add any number of simple, low-cost props. It's better to learn now and practice moving with natural motions. That way when you're feeling up to training hard you'll have a pretty good foundation.

I mean you're going to do it at some point anyway, unless you plan on sticking with machines (which, once again, is far more dangerous than using free weight, contrary to whatever you may have heard). It's actually pretty hard to injure yourself with free weight unless you drop it on yourself, which isn't really an issue except in olympic style lifts (that most people will never perform). It also translates much, much better to your work, especially in terms of prevention of injury, and does a lot more to strengthen your bones and joints (which I alluded to earlier when I mentioned your being a woman specifically, though it does apply to everyone).

Yes, there were similar machines available, and like I said, I had just finished 10 reps, and usually wait 30 sec (or less) in between sets. I would have been done in a minute, I don't think that's an unreasonable amount of time. It seemed that he didn't necessarily want to use it for himself, he was eager to show me "the right way." I let him show me, then I tried again, and I walked away when I was finished. I think he was offended that I didn't keep working on it with him, but I was finished with that machine, and wasn't there to socialize. I realize he was just trying to be friendly, but I'm a very shy person. If I don't understand how something works, I'll ask. I don't bother anyone else when I'm working out, so I would appreciate the same courtesy, I guess.

As for your thoughts on free weights... I appreciate the suggestions, and I'll take that into consideration. If I ever decide to cross over, I'll update with many questions, I'm sure... but for now, this is what is comfortable for me. All in all, it's better than sitting on the couch, so I'm happy as long as it's working.

Is it possible that you are trying to do cardio at too high an intensity? Basically, in doing cardio exercise, you could do it either aerobically (low to moderately high intensity) or anaerobically (highest intensity). The dividing line is usually said to be around 80% of maximum heart rate, but that depends on the person (and maximum heart rate may vary from the common formulas like 220 minus age for different people).

Within the aerobic zone, you should be able to do cardio for long periods of time, limited mainly by glycogen reserves (perhaps an hour for a typical person not on a low carbohydrate diet, more for someone who carbo-loaded or has trained himself/herself for endurance events).

Doing cardio in the anaerobic zone can only be done for short intervals or sprints. That is why some people like to do high intensity interval training (HIIT), where you alternate short periods of all out effort with periods of easy effort (well down into the aerobic zone).

If a heart rate monitor is available, you may want to see how fast your heart is beating while you do cardio, and what intensity you can sustain for long periods of time, so that you can plan your cardio based on that. If you want to go long, you need to stay in the aerobic zone; if you want to go all out, you need to do it for sprints / HIIT.

You may want to ask cardio specific questions in the Running and Cycling section (and HIIT specific questions in the HIIT section).

Regarding weight training, as another poster said, it will help you maintain muscle better if you want to attempt to lose fat. If you have difficulty doing weight training properly, you may want to ask specific questions in the Weight Training section. Given that your lack of strength is impacting you functionally (as you mentioned lifting patients and such), maintaining it and increasing it should be a high priority.