There's a scene in the TV series "The Big Bang Theory" where Sheldon goes to the movies, sits down, and yells. He then gets up, finds another seat, and yells again. Everyone stares. No one knows what to expect. And it goes on like this.

"He's finding the acoustic sweet spot," Leonard says, explaining the perpetually odd behavior of his roommate. And while that may sound funny, or sad, or creepy, or otherworldly annoying, it's what many of us do with fitness.

There's nothing wrong with experimenting like this, of course, because once you find your fitness sweet spot -- just like the acoustic sweet spot -- you'll feel better than you ever have -- and the movie will instantly thrill more. It's just that finding it often takes longer than we like it to. And sometimes people stare.

Whereas I may feel my best training 90-minutes a day, five days a week, you might think that's a warm-up. Or a death sentence. So how do you know where to start? And how do you know when you're not doing enough? Or when you're doing too much?

Are you eager or distant

If you're not excited to train, chances are you're not in your fitness sweet spot.

Now don't confuse apathy with loathing the WOD; that's different. You can still totally be keen to train and hate that horrible Assault bike. But if you're really dreading the idea of any activity, chances are you're doing too much. Or too much of the wrong kind.

Are you sore or hurt

Sore is a sign you're alive. Enjoy it.

Hurt, however, is a whole other story. Hurt means you're knocking on injuries door and you're about to step over the threshold. Hurt means you have hot knees -- about to become nuclear knees -- and instead of scaling, you keep pushing. Unlike sore, hurt is a warning.

Instead of crossing that line, error on the side of caution. When your knees feel sketchy, swap running for rowing, or use an empty bar, or God Forbid, spend an hour stretching.

Are you intense or dull

Far too many fitness enthusiasts mistake volume for intensity, and then they wonder why they don't see results. Simply put; intensity exactly equals results.

It's not about doing more work, and it has never been. It's about doing the most intense work possible for your current level of fitness, then sitting back and reaping the rewards.

If you've consistently added time -- even extra days -- to your workout routine, try backing off the volume and boosting the intensity. If you feel great, performance increases, and your mind clears, then you'll forever know that the secret to getting what you want out of your workout, is precisely related to how much effort you put into it.

Finding your fitness sweet spot takes time. But once you do, it gushes into other areas of your life like a volcano. Relationships improve. Work is more satisfying. Creativity skyrockets. And everyone will stare. Let them. They're just jealous you found the best seat in the house.