>>I don't disagree, but when I've tried this I just find myself doubly exhausted: once (mentally) from the work, and again (physically) from the gym.

When you walk into the gym you need to stop thinking about work and start focusing on your workout. For me, this comes in the form of planning which exercises I'll be doing, how much weight I lifted the previous time for how many reps, and how much I can increment it. And then during the lifts, I focus on the mind-muscle connection to make sure my form is correct and I'm activating the right muscles.

Trust me, when you do it like this, it's incredibly relaxing from a mental perspective. I actually look at my gym sessions as meditation time.

I have pretty much the same mentality and I Have to agree that it just works. It doesn't matter what I have on my mind before going to the gym as it is soon replaced by "I have to squat 2.5kg more than the last time?!".

I certainly agree with your comment about sleep. For me, I generally lump sleep in with my exercise because I've been strict about getting a minimum of 7 hours of preferably uninterrupted sleep in order to maximize recovery from exertion. The sleep and exercise combined work wonders to clear out the stress of the day. And while I feel exhausted after a workout, it's more of a calm, peaceful, and cleansing exhaustion.

I would hazard that you are coming to this from a relatively sedentary point of view. Often overlooked is the huge hump to get over before exercise starts showing it's benefits. It can take months if you do not have the strength it takes to work out effectively, or are performing less than optimal exercise routine, such as one focused on cardio.

A less than optimal exercise routine is entirely possible. Do you have any tips? Bad technique or not enough variety is certainly a concern, especially when working out on your own. The trouble is, when I try to find alternatives, they usually seem to require a significant time and/or money investment which I can't do right now (e.g. getting a personal trainer, or adhering to strict regimes). If there any any simpler resources out there I'd be happy to hear about them.

I have gone for half a year or longer exercising on average 5 times a week, sometimes more. Excercise is often physically draining for me afterwards. My experience is opposite of it taking a "long time to [feel?] benefits": it just takes 10 pushups to a 7 minute circuit workout for me to feel great and invigorated. A longer workout often leaves me feeling drained in the hours after. My circulatory system might feel much better, but my body feels tired.

Not all exercise sessions are made equal. If you're just doing 10 pushups or 7 minute circuits for 6 months, you're still very much in the beginner phase.

It took me a few years of consistent intense training to really get into the groove of things. I've been at it for about 9 years now. This is the intensity that I aim for (mind you, this is not me in the video): http://www.youtube.com/watch?v=LAhNyvTF5Uw

After that level of intensity on a consistent basis for a few years, you adapt to it. While you may feel tired, you gain energy from it as well.

I did much more than 10 push-ups or 7 min circuit training each session for those six months (and those six months isn't the only time I've exercised, just one of the longer uninterrupted streaks of it). Don't patronize me.

Not trying to patronize you at all, and I apologize if it came off that way. I'd say that most people in the tech/hacker community aren't too well acquainted with consistent, dedicated exercise. It wouldn't be unreasonable for someone to have the belief that after 6 months of 7 minute circuits, their body should be well adapted to intense workouts. Since I don't know who you are or where you stand on the experience spectrum, I took an educated guess, and apparently was wrong.