How Strong is Strong Enough?

You regularly hear how important strength training is in developing a good vertical jump. Most good sports training books and sites including this one have numerous articles devoted to the topic of strength development, scientific studies often show a high correlation between strength and vertical jump capability, and most reputable vertical jump programs including our own Vertical Jump Coaching have a strength training element to them (in the case of our Vertical Jump program though there is only a strength component if you actually need it!).

Still, the role of maximal strength training for vertical jump improvement is one that causes a great deal of confusion, so today I will explain just how it works, and how it needs to be incorporated into your vertical jump training.

The Role of Strength in Jump Height

Before I get into it, I think it is a good idea to have a quick refresher at the way strength factors into how much jumping power you can produce.

As a reminder the mathematical formula for power is:

Power = (Force x Distance)/Time.

This is often modified for practicalities sake to read:

Power = Force/Time

i.e. The more force (F) you can apply and the less time (T) it takes to apply it, the more power you can produce.

Maximum strength as it relates to jump height and power production can be said to be how much Force (F) you can generate and apply to the ground.

If for example you can exert 100 units of force into the ground in 0.5 seconds you can produce 200 units of power.

100/0.5 = 200

If you assume that you can apply the same % of the total force you can generate within the same time, then it is reasonable to also assume that if you hit the weights and get stronger than your power (and theoretically your vertical jump) should increase. For example, if you could now produce 125 units of Force in 0.5 seconds your power output would be 250.

125/0.5 = 250

vertical jump trainingNate Robinson: Power Personified

Where people often get into trouble, is when they put too much focus on weight training. If an athlete spends so much time lifting weights at the expense of their jumping and other explosive work it can lead to a situation where they are getting stronger in the gym but without increases in jump height.

How does that happen? It happens when the athlete gets stronger but they also get slower.

In this instance their strength goes up but power output might not. Mathematically it might look something like this:

125/.625 = 200

Here the athlete got stronger and could produce 125 units of force, but because of all the weight training, they lost the ability to generate that force as quickly (from 0.5 seconds to 0.625 seconds in my hypothetical example) and so power output stagnated.

If Only It Were That Simple

While my example above is all well and good from a theoretical standpoint, the reality is that quite often you CAN get stronger without sacrificing speed. This is especially the case when people are in the earlier stages of strength training.

The two main reasons for this is that beginner athletes (and to a lesser extent intermediate) have so much available potential to increase their strength through resistance training that these gains tend to come more quickly compared to a more advanced athlete, and as such not as much time is spent using comparatively slow movements such as squats, deadlifts and so on.

As you get more and more advanced with your training the rate at which you see strength gains tapers off. This results in the athlete needing to spend increasingly more and more time and effort in the weight room to keep getting the strength improvements.

With this in mind it isn’t difficult to imagine a scenario where someone new to vertical jump training who doesn’t have much of a strength training background might start off doing nothing but pure strength work and still seeing excellent gains in their vertical jump.

When this happens, it is easy to see how an athlete can start to think that an increase in strength will automatically think it equals an increase in jump height.

However as they continue to improve beyond the beginner stages though, the rate of strength gains and therefore vertical jump improvements will start to decline. The natural inclination at this point might be to think that MORE focus into strength training is what is needed as this is what got the results previously.

Of course, this would also be wrong.  At some point more strength really does come at the expense of speed and as per my example above, the athlete will just become stronger without further improvements in jump height.

Why Do You Get Slower After Too Much Strength Training?

The reason that an athlete can get slower is that in the absence of power and speed work their rate of force development declines. This is because your body adapts to the type of training stimulus you give to it. If you are constantly lifting weights in a reasonably slow and controlled manner, your body starts to adapt by allowing you to only generate force in a slow and controlled manner.

Now interestingly there has been some research that indicated that even when lifting weights you can still improve rate of force development by ensuring you have the intent to move the load fast. While this may be true, it still isn’t as effective as actually performing exercises that are closer to the desired speed required for maximum jump height.

So How Do You Know When You Are Strong Enough?

The best way to determine how strong is strong enough is to keep a track of your strength gains and see how they are impacting your jump gains. If your vertical jump gains start to slow down even though your strength gains are continuing to go up, that is a pretty good indication that you are no longer applying the extra force to your jumps in the short time frames required.

This is to say that you have a large explosive strength deficit. As those of you who have read the FREE vertical jump training guide will recall the explosive strength deficit is the difference between how much force you can generate in an unlimited time and how much you can generate within a desired time frame (which for jumping is usually very quick).

When strength gains are failing to carry over to jump gains it is best to change your training focus and put your strength development into a maintenance phase and devote more effort to explosive jumping movements and plyometrics. This shift will provide the necessary stimulus to help reduce the explosive strength deficit.

This works both ways too. Once your gains from the plyometrics and jumping based work start to slow down then it is also possible that your body has currently peaked in its ability to produce muscular power and the solution for this is to then switch back to a block of more intensive strength work and shift the plyos/jumping work to maintenance loads.

The Explosive Strength DeficitThe Explosive Strength Deficit

As readers of this site and our FREE VERTICAL JUMP TRAINING GUIDE will know, the secret to getting the best gains is to work on your weaknesses. The example graph is a simple illustration of that philosophy and the explosive strength deficit example in action.

As you can see there are several periods where jump gains plateau but strength continues to increase (large explosive strength deficit). At these points the athlete will maintain strength but focus on explosive jumping work to allow jump gains to continue until the ESD has narrowed again. It shows that your needs change over time and why you need to adapt your training to those changes in order to get the best results.

This is exactly what our vertical jump program does by the way. It is also the reason that having a custom jump training program provides far better results than a pre-written cookie cutter type program.

Can You Be Too Strong

At some point you could become so strong that no matter how much plyometrics and jumping you did you would still never be able to apply anywhere near the total amount of force you can generate within the time it takes to execute a jumping motion.

Where that actually occurs though is open to speculation and highly dependent on the individual, but of the numbers I have seen thrown around the most common theory is up around the 2.5XBW squat mark.

I actually put the 2.5XBW in here with a great degree of trepidation because I know that inevitably some readers will look at that and think to themselves – “great, I can just keep squatting and lifting until I can squat 2.5X BW and I will still be able to make good jump gains!”.

This however is NOT the message I am trying to convey. For starters do you know how freaking hard it is to get your squat up that high. Seriously, even if you are squatting 1.5X BW now, you could go away for 12 months and do not much else but work on it and still not reach that level.

strength trainingProbably Strong Enough!

Secondly, in order to get maximum carry over to your vertical jump you have to keep doing jump training regardless of whether or not strength is your biggest weakness. What I am trying to say is that it is okay to keep getting stronger, but if vertical jump improvement is your primary goal, you need to monitor how that is going as a priority over chasing numbers in the weight room.

Train Smarter For Faster Vertical Jump Gains

While the theory behind increasing your vertical jump isn't that complicated, the difficulty comes in applying that theory to you as an individual. The real secret to getting the most inches om your vertical jump out of your training is knowing what you need to be working on (strength, speed, technique?) at any given point in time.

And this is where our jump coaching service comes in. With over 10 years working with 1000's of athletes around the world I have developed a simple system of assessing an athletes strengths and weaknesses and writing specific, 100% individualized training programs to help athletes just like you to improve their vertical jump in the quickest time possible.

When you start focusing your training onto the things that you need to work on the most your vertical jump will improve at the fastest rate. If you want to improve your vertical jump as rapidly as you can then you really should sign up to my vertical jump coaching program today.

For more information click on the image below or follow this link.


I will finish this article by stating categorically that I love strength training for athletes. It is fun to do, you can throw in some bands and chains for variation, but most important of all, getting stronger DOES result in vertical jump improvements. Up to a point.

To make the most of your hard work it becomes imperative that you monitor your progress to determine when it is the right time to switch gears to a more explosive/plyometric based program (or if you are using our vertical jump coaching service, we will do this and will adjust your workouts for you).

SO how strong is strong enough? Strong enough is when strength gains no longer translate to improvements in jump height. If you keep that in mind as a good rule of thumb, it should help guide you in the right direction with your training.

Related Articles

Strength Training Part 1 - Getting strong is vital for jumping high. Part 1 of our 2 part look at strength training covers the various theories behind strength training.

Reactive Strength Part 1 - What is reactive strength, why is it important, and even better, how do you train for it.

How To Slam Dunk - How to slam dunk. Breaking down the fine art of dunking a basketball.

Vertical Jump Training - The quickest way to increase your vertical jump.


Download our FREE REPORT and gain 4 inches on your vertical in 4 weeks!