"I didn't realize something so small could be so impactful!"

Those were the words that Mila Kunis uttered to me, her silky brown hair plastered against her glistening forehead, while we rolled around in the sack.

"Seriously, Dan, what are you? Some sort of exercise Yoda?"

With that I snapped out of my lovely daydream and realized that I was standing in the middle of the training floor. And these words were not being spoken by the Sexiest Woman Alive, but rather a 7-foot tall pro athlete during our training session.

Well, at least his forehead glistened, too.

All I did to convince this baller that I was an exercise Jedi was to move his arm position slightly during a decline EZ-bar triceps extension – a small tweak that not only made him feel the movement more, but actually made the exercise more effective.

In today's "functional fitness, suspension training, circus act, make-up-a-new-exercise-every-time-you-go-into-the-gym world," I love taking tried-and-true old school exercises and adding little tweaks to make them that much more evil, and much more effective.

Here are my 7 favorite variations. Put them into your routine and you'll quickly understand what I'm talking about.

1 – Biceps Curl

This is a move I ripped right out of bodybuilding legend Vince Gironda's playbook. When most people get near maximal load while performing standing biceps curls, they tend to 'cheat' the movement by using body English and momentum to swing the bar up.

I've never understood this school of thought. The biceps curl shouldn't be a move-the-most-weight-at-all-cost strength exercise in the same way a Max Effort deadlift or bench press might be. In fact, I'd argue that most people are doing biceps curls to get – drumroll, please – bigger biceps.

This is why I love the perfect curl. It actually reverses the typical cheaters movement and places more emphasis on the biceps muscle itself, making it a great hypertrophy exercise.

Start in a standing position holding a straight bar, EZ bar, or dumbbells in front of your thighs with your arms extended. Lean your torso back 5 to 10 degrees. As you curl up the weight, begin moving your torso so that you're leaning forward 5 to 10 degrees by the time the barbell reaches your collarbones.

Be warned, you'll have to use significantly less weight doing the perfect curl than you are used to using with cheat curls. This will likely lead to your training partner making fun of you. If this happens, just use your newly developed biceps to put him in a guillotine choke. Problem solved.

2 – Skull Crusher

This is the tweak that got my hoops player's triceps all fired up. I like to use an EZ bar and a decline bench for skull crushers. The normal way to perform these would be to lie back on the bench, press the bar up towards the ceiling, and then bring the bar down between the bridge of your nose and hairline.

But by moving your arms five degrees towards your head in the top position (and making sure you keep them there for the entire set), you'll be keeping your triceps in a stretched position for the entire movement. This sucks in that really, really good kind of way, like watching Showgirls when

3 – Barbell Roll Out

I'm a huge believer in training the core with a variety of methods – flexion, extension, rotation, anti-rotation, isometrics – they can all work as long as they're intense enough to meet the needs of the trainee.

What I mean by this is if you can front squat 315 for 6 reps, you probably don't need to be holding 30-second planks. Your core is already stronger than that.

The same is true with barbell or ab wheel rollouts – once you can do 12 or 15, there's probably not much benefit to simply adding reps. That may lead to fatigue but probably not strength.

Instead do what I call the half-barbell rollout. Usually when you shorten the range of motion of a lift you make it easier. With the half-barbell rollout, the opposite is true. By fully extending out and only rolling back halfway (instead of all the way back to the knees), you keep full tension on your core musculature, making it much tougher to get through a 10 or 12 rep set.

Still too easy for you? Add a 3-second pause when you're fully extended.

4 – Hamstring Curl

I won't get into the whole "is the hamstring curl a functional, worthwhile exercise?" debate. However, I will say it's an easy way to overload the hamstrings through knee flexion.

I don't know a bigger advocate of the hamstring curl than Charles Poliquin. Not only do they frequently appear in his programs, he's come up with more variations of the hamstring curl than Lindsey Lohan has arrest warrants.

For a painful twist, try performing them with your toes plantar-flexed (pointing away from your shins) and internally rotated. This will take your calf muscles out of the movement and isolate what's often the weakest part of your hamstring. Prepare to be humbled.

5 – Step-Up

Not enough people put step-ups in their programs. If I saw as many lifters doing step-ups as banging out sets of heavy shrugs, the world would be a much sexier, bigger-legged place.

Instead I rarely spot anyone performing this great overall leg builder, and when I do they're usually doing them the easy way.

Quality step-ups require that the lead leg (the one on the bench or box) do the vast majority of the work. Yet most people pogo up off their back leg, making this movement way too easy.

Try performing your step-ups stiff-legged, where you lock out the knee of the back leg and drive the toes of the rear foot into the top of your sneaker (so only your heel is on the ground). Brutal.

6 – Lateral Raise

If you read T Nation regularly, you'll know that most programs involve too much pressing and not enough pulling. Combine that with the fact that many are hunched over computers for 14 hours a day and you have a recipe for tight and overdeveloped anterior (front) deltoids paired with weaker posterior (rear) delts.

So what's a bench press-loving meathead to do? How about incorporating more posterior deltoid recruitment into your favorite shoulder exercises? In this tweak to the lateral raise, make sure that your pinkies are always above your thumbs.

To help you do this, picture yourself as a Greek God pouring water out of a clay urn as you lift your arms. What, you're not into art history? Feel free to come up with whatever visual techniques you like.

7 – Romanian Deadlift

Adding pauses in disadvantageous positions is a simple and very effective way of driving up the intensiveness of most any movement. If you want to make your glutes, hamstrings, grip, and mid-back suffer more than being locked in a room with ten pre-teen girls and a Justin Bieber CD on repeat, try this multiple-pause Romanian deadlift that I got from strength coach Ed Williams.

As you lower the bar, add a 2-3 second pause at the mid-thigh and then another 2-3 second pause at the end range of motion. Not evil enough for you? Add in another 2-3 second pause at the mid-thigh on the way back up.

If you have a hard time sitting down on the toilet for the next week, don't say I didn't warn you.

And I'm Out!

Okay, Champ, you're all set. Seven tweaks that will make your exercises more evil than the devil, zombies, and that red-headed plastic horror movie doll that comes to life combined. I'd love to hear about your most evil exercise variations in the Forum.