Strength training: tuning velocity losses for maximal gains

As we’ve stated so often in numerous previous articles, the performance benefits of strength training for athletes as part of an overall program are hard to overstate, regardless of your sport. In a nutshell, the question is not can you afford to invest time and effort to strength time, but can you afford not to! However, strength training takes time and energy so it makes sense to strength train in a way that produces the greatest benefits but with a lowest reasonable amount of time and effort. This explains why researchers have devoted much attention in recent years to investigating the best and most efficient approaches to strength training structure.

New concepts for determining reps per set

The traditional resistance training approach for athletes has used a structure based on a fixed number of repetitions per sets based on the athlete’s ‘1-rep max’ (1RM – the highest weight that can be lifted using excellent form and technique) for that exercise. So for example, if the athlete’s 1RM for the overhead press is 60kgs and strength/power gain is the goal, the weight might be set at 80% of 1RM (48kgs) and a defined number of sets consisting of 4-8 reps per set of overhead presses are performed using a weight of 48kgs.

This traditional approach has stood the test of time because it works – even when different percentages of 1RM loadings and reps per set are used⁽¹⁾. The question in the context of efficient strength training however is whether the traditional approach is best? Are there better ways of structuring a strength session that produce good gains for less effort, and if so, what are they?

Velocity-loss training

One approach to structuring sets and reps that has become increasingly popular over the past three years or so is ‘velocity based training’⁽²⁾. As Andrew Sheaff explained in an earlier SPB article on this topic, with a velocity-loss (VL) approach, training sets are not performed with a pre-determined number of repetitions. Instead, the velocity loss (ie slowing of the exercise movement during the lifting phase) over the course of a set will determine when the set is finished. Once a certain percentage of the initial speed is lost, the set is over. For example, if the initial reps are performed at 1.0 meters/second and the goal is to limit velocity loss to 20%, the set will continue until the athlete can no longer maintain a minimum velocity of 0.8 meters/second.

Velocity loss is therefore really a measure of how much fatigue has been generated over the course of the set. As greater velocity loss implies greater fatigue, measuring the velocity loss is really about measuring, and controlling, fatigue. Controlling and limiting fatigue during strength training enables the quality and the speed of the movement to be maintained. This should in theory have benefits for athletes, especially where the power and speed of the movement is important (for example in sprinting and jumping performance) – something that has been borne out in research that found velocity losses of 10-20% were preferred to higher losses^(3,4).

Light load training

Much the research into velocity-loss training has looked at how training with different velocity losses (remember, greater velocity loss come from performing more reps per set, accumulating more fatigue and trying to work closer to complete failure – equivalent to 100% velocity loss) impacts strength and performance gains. Quite naturally however, most of these velocity loss studies have been conducted using the kinds of heavy-ish loadings commonly used in traditional strength training – ie around 80% or so of 1-repitition maximum. But what about when training with lighter loads - for example as a novice trainer, or when returning to strength training (eg after an injury)? What kind of velocity loss threshold produces the best gains then?