How do strength gains transfer to sport?
If you enjoy this article, you will like my first book (see on Amazon).
When you work with athletes, you want to be sure that your strength training programs are going to improve their sports performance.
And if you want to help your athletes win, then you need to believe that your strength training programs are better than those written by other strength coaches!
Of course, we all like to believe that what we are *already* doing with our athletes is “the best way” of training.
But in reality, we have no way of knowing whether a different approach would be better than what we are currently doing, because so much is changing while we are trying to take stock of what is going on.
Individual athletes develop over time, some arrive and others leave, and the conditioning, sports, and tactical training programs are changing constantly. So it is nearly impossible to compare the effects of one strength training program to the effects of another, while also delivering them.
So how can we get a competitive advantage?
Well, an easy way to get an advantage is to spend more time thinking about how strength training actually transfers to sport.
And the best way to start doing that is to look at how the strength gains achieved in one movement or exercise (like a squat) do actually *transfer* to force production in another movement (like jumping, sprinting, of changing direction).
How do specific strength gains transfer to other movements?
Strength is specific, which means that the gains in strength achieved in an exercise are always greatest in the exercise used in training. Even so, there are also strength gains in other, untrained exercises or movements, but they are smaller.
The degree to which strength gains are observed in an untrained exercise or movement after strength training is called “transfer.”
Transfer depends primarily upon the similarity between exercises and movements, across *all of the ways* in which strength is specific, and not just the movement pattern. However, since the movement pattern is the easiest one to see, this tends to get talked about most often.
Similarity between exercises and movements
Once the concept of “functional movement” took off, many strength coaches stopped talking about how to figure out which exercises transferred best to which sporting movements, because it was assumed that the movement pattern was the only thing that mattered.
In fact, while the movement pattern is important, there are other factors that make a bigger difference.
Within the framework of ways that strength is specific, there are 8 ways in which strength can produce targeted effects, as follows:
1. eccentric and concentric phases
2. velocity
3. joint angle of peak contraction
4. point on the strength-endurance continuum
5. degree of stability
6. external load type
7. force vector
8. muscle group
Using this list of key ways in which strength is specific, we can analyze (1) the trained exercise (e.g. the heavy parallel squat) and (2) the sporiting movement that we want to improve (e.g. change of direction ability), and then we can figure out how well we think one might improve the other, which we can refer to as the amount of “transfer” that occurs.
Example: change of direction ability
It we analyze change of direction ability, we will find that it is primarily determined by the ability to decelerate quickly, with the quadriceps (knee extensors) playing the main role (and the hip extensors a lesser role), while lengthening and producing high forces at moderate muscle lengths, with force being directed horizontally.
Additionally, a secondary factor is the subsequent ability of the same muscle groups to exert force quickly while shortening in the acceleration (concentric) phase in either horizontal or lateral directions.
There is indeed some good correspondence between the heavy parallel back squat and some of the characteristics of change of direction ability. This is probably because the heavy parallel back squat is primarily a quadriceps exercise, and secondarily a hip extensor exercise, and the parallel squat position does work these muscles predominantly at moderate-to-long muscle lengths.
However, the heavy parallel back squat does not incorporate all of the key characteristics we need. In fact, it lacks the following essential requirements for improving change of direction ability:
- Deceleration — the heavy parallel back squat does not train the lowering (eccentric) phase of the movement very effectively, which is key for deceleration. This is because we are approximately 125–150% stronger when lowering a weight than when lifting it, so we are unable to lift a weight that is heavy enough to challenge us (and therefore produce eccentric-specific adaptations) when lowering it.
- Speed — the heavy parallel back squat does not use a high speed in the acceleration (concentric) phase of the movement, because the weight is too heavy. And this is a key feature for improving acceleration during the change of direction maneuver.
- Direction — the squat uses a vertical direction of force to lift a weight against gravity, while the change of direction maneuver requires horizontal and lateral force production.
To create a training program that improves change of direction ability more than just a parallel back squat, we can do two different things.
Firstly, we can change the type of resistance used to make the eccentric (lengthening) phase more challenging for the knee extensors (and hip exensors), by using a flywheel squat or an accentuated eccentric parallel squat with weight releasers.
Secondly, we can mix in other exercises as well. Jump squats could provide a high-velocity stimulus for the acceleration phase, hip thrusts can provide horizontal force production (especially hip thrusts with eccentric overload, either with a partner, or using two legs to ascend and one leg to descend), and diagonal and lateral lunges can develop the ability to produce force in other directions.
What is the takeaway?
Identifying which exercises, and types of resistance, transfer best to sporting movements is a puzzle, but it is not an unsolvable puzzle for strength coaches who are prepared to look in detail at the biomechanics of the athletic movements they want to improve. Using the framework that strength is specific allows us to identify which exercises will help athletes improve their performance best, and provide real competitive advantage.
If you enjoyed this article, you will like my first book (see on Amazon).
