One of the most commonly overlooked loading parameters is tempo, or lifting speed. It relates to the “time under tension” of an exercise. For those who are still unconvinced of the importance of training tempo, here are five good reasons – complete with peer-reviewed scientific references – to change your mindset.
1. Vary Tempo to Overcome a Plateau.
Varying tempo, or changing the rate at which you perform the different parts of a lift, is an excellent way to overcome a plateau and shock the body into adapting. Time under tension governs the amount of stimulus a muscle is exposed to.
For instance, performing a set of 10 repetitions of squats with 60 kg at a 1-second-up and 1-second-down tempo is quite different from the same weight and reps at a 1-second-up and 4-second-down tempo. The difference is in the time exposed to tension. The first variation takes 20 seconds, while the second variation takes 50 seconds. That is a 30-second difference in the time the muscles are exposed to the weight.
In prescribing tempo, four numbers are used like this: 4210. The first number dictates the seconds it takes for the eccentric or down motion; the second number is the pause before the concentric motion, which is the third number; and the fourth number is the pause before the repetition repeats.
In the case of a 4210 tempo in the bench press, it takes 4 seconds to lower the weight, there is a 2-second pause, then the weight is rapidly pushed up in 1 second and the rep starts over immediately.
You should change the amount of time spent on different phases of a lift because it increases intramuscular tension and provides a new or different type of stimulus to the muscles. It is a great way to stimulate further strength development once the body has adapted to a rep range or set range and isn’t making progress. Plus, varied tempo is an ideal way to train for hypertrophy and strength at the same time.
2. Train Different Energy Systems and Get More Adaptation.
Not only should you vary tempo within a lift, but you should also use different lifts that naturally have distinct speeds for optimal training results. Explosive, ballistic contractions such as Olympic lifts bring about more central nervous system adaptations, while slow-speed lifting with varied eccentric and concentric time phases bring about more metabolic adaptations, such as increases in muscle glycogen, creatine phosphate, and ATP. A combination of high- and low-velocity training produces greater strength and body composition results than either one alone.
Muscle adaptations are also facilitated with varied time under tension. One study found that increased time under tension resulted in greater muscle fatigue due to impairments in muscle contractile properties. By increasing neuromuscular fatigue through a variable tempo, researchers suggest that superior strength and hypertrophic gains can be made as long as the load lifted isn’t compromised.
3. Target High-Threshold Motor Units with an Isometric Pause.
High-threshold motor units are the fast-twitch or powerful muscle fibers. An excellent way to target them is with an isometric pause in the advantageous position (where the body is strongest based on lever length).
For flexion exercises, such as biceps or hamstring curls, you should pause in the down position for 1 to 2 seconds. For extension exercises such as squats or bench presses, pause in the up position between the concentric and eccentric motions, when the limbs achieve near lockout position.
Of course, varying tempo allows you to perform an isometric pause in the disadvantageous position when you have poor leverage as well. The disadvantageous position for flexion exercises is the up position, and for extension exercises it is the down position.
You can imagine that holding the bottom position of a squat for 1 or 2 seconds would provide a valuable training stimulus while increasing intramuscular tension, a combination that can further boost strength development.
Take note that it is necessary to train high-threshold motor units and develop maximal strength in slower lifts such as the squat, deadlift and bench press in order to improve faster on movements such as Olympic lifts.
For example, you cannot power snatch 100 kg unless you can squat about 184 kg. If you can back squat only 160 kg, you won’t be able to snatch 100 kg until you increase your squat weight significantly. Varying tempo is an ideal way to work on this.
4. Recover Faster with a Varied Tempo.
Research shows that it’s possible to increase your time under tension and perform a high volume of work by using two bouts of varied resistance speed. A recent study found that performing a slow-velocity exercise – in this case about 4 seconds for the eccentric lowering phase of the biceps curl – followed by the same exercise done with fast velocity (called the “repeated bout group” in this study) will reduce muscle damage and allow for a faster recovery than just performing the fast-velocity exercise (called the “single bout group”) alone. The repeated bout group had less muscle soreness after the fast-velocity exercise and recovered isometric strength and range of motion significantly faster than the single bout group.
Having less muscle damage and soreness can be beneficial if you need to recover quickly in preparation for competition or because you want to perform a subsequent workout that is more demanding and yields increased soreness.
This study illustrates both the value and effect of varying tempo: Different tempos require the body to adapt in different ways and cause unique metabolic and neuromuscular results. In addition, varying tempo with repeated slow- and fast bouts allow for larger volumes of work to be performed with less muscular stress than the smaller volume that would be performed with just a set of fast-velocity contractions.
5. Match Resistance Curves to the Human Force Curves with Chains and Bands.
An excellent way for more advanced lifters to overcome plateaus and vary tempo is to train with chains or bands attached to the barbells. This strategy is particularly effective in working the extensor muscles because attaching chains to a barbell will vary the amount of resistance your muscles have to contract against.
For example, if you put chains on the ends of the barbell when squatting, the chains will pile up on the floor during the eccentric or down portion of the lift, decreasing the weight. As you come up from the squat during the concentric phase, the weight will increase as the chains come off the floor and contribute to your load. This is effective because it increases the weight during the weaker movement (you have less force capability concentrically), requiring you to train through the sticking or most challenging point of the lift.
A study of college football players found that the athletes significantly improved maximal strength and peak power from training with chains and bands. The players who trained with chains and bands improved their 1RM bench press by 10 kg versus players who did a traditional bench press and improved by only 7 kg after a seven-week training program. Researchers also noted that weighted chains supply the added benefit of training the stabilizer muscles because they swing and oscillate throughout the range of motion of a lift.
You can use variable resistance on exercises such as deadlifts, squats and bench presses or any exercise in which your progress has stagnated and in which you can reasonably attach chains or bands to the barbell.
Eccentric hooks (weights with hooks that hang off the sides of a barbell and drop off once the bottom of the dangling hooks hit the ground) load the lift in the opposite way, making the lift heavier during the eccentric down portion of the lift, where you are naturally stronger. The hooks come off and you can then explode up with less resistance in the concentric motion. Be sure to limit variable resistance training to only one workout out of two, at the most, because it is very taxing to the neuromuscular system.
If you don’t carefully manipulate all the loading parameters of training such as tempo, you cannot know exactly what type of training stimulus you are applying to the body. Take control of your workouts, and you will achieve your goals faster than you ever thought possible.