01/24/2011 10:28 am ET Updated May 25, 2011

Exercising Doesn't Need to Be Unpleasant

I'm a busy guy with a fair number of responsibilities, but I love my free time. Being absolutely unproductive, whether alone or with my wife, kids, and dog, at the beach or reading a book on the couch at two in the afternoon, is what makes life worth living. I imagine you're all pretty similar in that regard. It's what we're all looking for, after all -- to have gotten all the important stuff done so you can rest easy and simply be.

I've got enough work in my life to fill several, so when it comes to staying fit, healthy and strong, I'm not looking for a second job. I tried that for a couple decades as a marathoner and triathlete, and I was miserable (not to mention unhealthy and weak, but that's another article). I want the most bang for my buck. Yet when most people discuss fitness, they speak in terms of work. It's right there in the word: "workout." And since work is supposed to be hard and unpleasant, good workouts become long, dreary things, exercises in pain and suffering that you have to push through. No pain, no gain, right? It's all very Puritan. But is it true?

We certainly try to make exercise as unpleasant as possible. Consider how most of us work out. Jog for an hour (if we can muster up the will to do it), making sure to keep our heart rates at 80 percent of our max and jogging in place at stoplights (because stopping for even a second will halt the fat burning). Lift weights, using complex machines that isolate the most important body parts, like biceps, forearms and calves (you know, the ones that everyone can see), and subject our bodies to movement patterns they'd never face in real life.

Sure, our joints might hurt a bit and all that chronic cardio makes us gorge on pizza and ice cream, but that's just part of the deal. Sure, we dread working out, but that's normal -- exercise is supposed to be miserable, or else it ain't doing its job.

To decide whether the conventional advice regarding physical fitness is actually working, consider your average gym-goer. He or she is doing things the right way, putting in the time on the treadmill, hitting the separate body parts with resistance training, and yes, huffing and puffing and sweating, but with paltry results. Note the persistent belly fat, the magazine to keep the boredom away and the agony off the mind, and the sad eyes fixated on the television for digital escape. And that's just the person who actually goes to the gym. There's also the flood of newcomers every January who go a few times, maybe a few weeks, and never return. You know it's true; we've all noticed the New Year's gym influx and subsequent exodus. Something isn't working. There's something about the way we exercise that squanders results and makes people hate working out. It's both unsustainable and ineffective.

To figure out how to fix the problem, let's go back to the concept of work. What is effective work? Is it short and to the point or long and drawn-out? Who's the better worker -- the one who gets his report done in four hours working diligently or the one who takes seven hours to complete the same task? Obviously, to produce the same result in less time is of greater value for everyone involved; this is self-evident for schoolwork, physical labor, and the workplace, and yet when it comes to physical fitness we forget all about the concept of time economy. We confuse length with intensity, when the opposite is true: excessive quantity of exercise necessarily diminishes intensity, and thus quality, of exercise.

Workouts shouldn't be long and awful, then. They should either be hard and fast and even fun, or really long and leisurely. I always say that you should make your long, slow workouts even longer and slower and your short, fast workouts even shorter and faster. Don't jog for 45 minutes at a high heart rate, plodding along as you try for intensity but never really reach it, stressing your adrenals, and prompting the release of excess cortisol that in turn increases carb cravings, belly fat and muscle wasting; walk or hike, instead engaging in low level aerobic activity that slowly burns fat and, most importantly, makes exercise pleasurable and relaxing. Save your intensity for the truly short workouts where you can really push yourself.

Like sprinting. Sprint once in awhile. Once a week, run six sprints at top speed -- remember, a sprint is a max effort by definition -- with plenty of rest in between. Cut the sprint short when you start to slow. You're done in about five minutes, your body is sufficiently stimulated, and you will get fitter and faster. It's hard, yeah, but it's over before you know it. If you can't actually run, consider swimming, cycling, even crawling sprints, which work equally well.

Strength training doesn't require complex equipment or machinery, or even a gym membership. Consider the world your gym and your body the equipment with gravity providing the necessary resistance. Free weights are excellent tools, but they aren't required for basic fitness and strength development. And when you work your body, consider that it is a single thing comprised of many working parts that work together to move you through space. Full body movements, like squats, pushups, and pullups are the most effective, the safest, and provide the greatest transfer to real life movements, not isolated exercises that segregate muscles and joints.

We're all busy people with packed schedules and multiple responsibilities, but we owe it to ourselves to stay fit, healthy and happy. Luckily, by pairing intensity with brevity, and length with leisurely movement, we can achieve all three goals at once.

Mark Sisson is a former elite marathoner and triathlete. He is the author of the best-selling health and fitness book, "The Primal Blueprint", and publisher of the health blog, Become a fan on Facebook and visit Mark's blog for daily health tips.