We’ve all seen it … the gym rat swinging heavy dumbbells and calling it “bicep curls”; or rocking back and forth with the full stack on the lat pulldown; or bouncing a heavy bar off their chest on a bench press, pounding out some fast reps. There’s also those people who treat weight training like “cardio” – firing off dozens of reps at lightning speed with very light weight.
What do they all have in common? Besides the fact that most of them are probably injured in some way, they are are all performing their resistance training at a fast tempo.
Now I admit that I’m generalizing when I describe everyone who performs fast reps as “ego-lifters” with crappy form… there are many experienced lifters who practice decent exercise technique but train with a faster tempo. However, the point of this article is to question whether that is the optimal way to train.
First of all, you need to ask yourself “what is the goal?” If you’re training solely for strength or power, or you simply want to add as much weight to the bar as possible, knock yourself out. I’m not criticising exercises that are intended to be performed explosively, such as the push press, jump squats, or Olympic lifting, if performed correctly for an appropriate goal. However, if you’re goal is to gain muscle or transform your physique (without getting hurt), then you had better slow the heck down!
There are numerous studies demonstrating the increased effectiveness of resistance training with a slower tempo (or repetition speed) for hypertrophy, even if that means using a lighter load. You can check out one such study on PubMed here:
=> High vs Low Velocity Resistance Training for Hypertrophy
Here are just a few of the many reasons I recommend lower velocity “lifting”:
- Greater Time Under Tension (TUT) – while not the most important factor for building muscle, more TUT is related to hypertrophy. By slowing down your repetition speed you increase the duration of each set, which leads to more total time under tension for the target muscle group.
- Better Form – although some people claim to be able to maintain strict form while performing faster reps, the fact is that when you slow it down a little you will have better control and a greater ability to focus on proper exercise technique.
- More Continuous Tension – The faster you move a weight the more likely it is that you will be using momentum to assist in moving it, which will unload tension from the target muscles at certain points in each rep. When you bounce, swing, or accelerate a weight force is generated with a strong impulse initially followed by a slight reduction in tension. However, when you perform slower, smooth, more controlled repetitions (without resting between reps) the tension is continuous leading to greater inroad to fatigue.
- Increased Muscle Activation – EMG studies demonstrate that when you move a weight more slowly with controlled effort and focused tension, there is greater activation of the target muscle. It is also much easier to focus on intentionally squeezing and strongly contracting the muscles you are training when you move the weight slower with concentrated effort. Moving the weight quickly leads to increased joint stress and decreased muscle fiber recruitment.
- Stimulate Fast-Twitch Fibers with Slower Reps – Lifting heavy weights at a slower velocity actually recruits the larger, higher-threshold “fast” muscle fibers. It is commonly thought that to work the “fast twitch” muscle one must move quickly, but this is not the case.
- Eccentric Emphasis – Studies show that lowering the weight (eccentric) is as important as lifting the weight (concentric) when it comes to causing muscle-cell “damage” (one factor related to hypertrophy). So when you lift the weight and then drop it quickly (letting gravity do the work rather than muscular effort) you are cheating yourself of some of the benefits from your training.
- Reduce Risk of Injury – This, in my opinion, is the most important reason of all. The faster you lift, the greater the risk of injury. Speed kills. When you combine training to volitional fatigue with heavy weights at a higher velocity, the risk of injury is even higher. This is just part of the reason why Crossfit is so notorious for having a high rate of injuries among it’s participants. It’s one thing if you want to risk injury for yourself, but it’s another thing altogether if you’re a trainer and you’re risking your clients’ well-being.
While you may need to use slightly less weight performing your repetitions more slowly (ie: 2 to 3 seconds concentric and eccentric), it is not necessary to use very heavy loads in order to gain muscle mass. Your muscles don’t know how much weight you put on the bar… they only know how much tension they need to generate.
One can argue that both high-speed movements and heavy resistance can stimulate hypertrophy, which is true. But the point is that using very heavy weights or fast reps is NOT necessary for building muscle. Muscle hypertrophy requires the stimulation and overload of the greatest number of muscle fibers. This can be accomplished by training with slow strict form to volitional fatigue. Extremely heavy loads are not required to achieve this, nor is the velocity of the movement a critical aspect.
Since you don’t need to train using extremely heavy weight or fast reps to build muscle and develop an aesthetic physique, it makes sense to avoid forces that exceed the structural integrity of your joints (tendons and ligaments) and increase the likelihood of injury.
The point is, if your goal is to get stronger and build muscle, while minimizing risk of injury – SLOW DOWN!
