move at the speed of heavy

"When weight training to gain size and strength, it is best to lower the weight slowly. The lowering phase is what tears the muscle fibers, thus stimulating a growth response." 

Does it matter how fast you move during a resistance exercise? Sure. But there's no formula. Slower does not equal better, as the statement implies.

Who are these by-the-book exercise people who actually implement a two second concentric (lifting) phase and a four second eccentric (lowering) phase? I appreciate their understanding of the academics, but moving that slowly looks ridiculous in almost any context.

[Excuse me as I go pick up my 1-year old daughter for 2 seconds, remove her from the bowl of dog food, and relocate her to another section of the living room with 4 second lowering technique.]

"Dad, what the hell?" 

It's true that the eccentric (lowering) phase of resistance exercise is key to muscle growth and, later, strength development. The magic lies in the fact that muscles are literally shredded (and likely quite perplexed) when you ask them to simultaneously generate lots of force and lengthen. Afterwards, you cut the muscle a break, and the repairing process begins.

But the duration of lowering is not the whole story. Guess what else shreds muscle fibers and stimulates the entire body towards growth and various awesomeness?

Loading! Iron! Heav-ey! Every muscle in in every person can move drastically less load with a 2:4- second rep than they can with a more functional and less weird looking pace of say, 1:3.

So the bottom line is that lifting slowly does provide a longer eccentric time under tension (good for stimulating more growth), but also necessitates a lighter load (not as good for stimulating more growth). And now we bring in the big guns to settle the dispute!

[Enter the Central Nervous System, strutting with lats flared.]

CNS is king when it comes to movement. The CNS derives more benefit from non pencil-necked rep speeds, and especially flourishes in the "survive or be crushed" tempo. Handling more weight and accelerating it quickly develops the fastest and largest number of high threshold, powerful, bigsexy motor units. Heavy loading and high speeds streamline neural drive to the muscles in numerous ways. Ways that actually mean something when you're trying to chase down a soccer ball or wide receiver or 90 mph fastball or curious toddler.

So the faster the better then?

Not really. Speed kills...if it means failing to control a massive load in any way, shape, or form.

Instead try this 4-step guideline to YOUR best rep speed*.

1. Step 1: Load the thing! After you have done time ingraining correct movement patterns. Warm up and then us enough weight that you don't have energy to worry about counting seconds.
2. Step 2: Lift it. Attack the movement with deliberately furious fury, as if you're going to throw/push/pull the resistance through the roof. In reality, the load moves relatively slowly because, again, the weight is heavy!
3. Step 3: Put it down. Don't throw down. Don't slam weight plates so everyone in the gym knows what rep you're on. Don't levitate/hover. Don't bounce it off your chest to test the integrity of your sternum. Lower it under control so you don't get injured. 
4. Step 4: Repeat
5. Step 5: Have a MASSIVE bucket of power to draw from, and apply to whatever it is you like to do.

*Results may vary. It will take more than 90 days...sorry P90 [blank] mentality.
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