You’re Slow Because You’re Weak


  1. Stronger athletes jump higher
  2. High levels of force produce high levels of acceleration and velocity
  3. Stronger athletes compete at higher levels of sport and perform better in explosive athletic measures
  4. Getting strong provides the base for speed and power gains

The Expert

Opine. verb: to express an opinion about something.

I used to be an expert.  You could have asked me anything about training and I would give you my opinion.  Although I wasn’t jacked or athletic, I always had the answer for how to achieve such things.  I knew just enough to think I knew it all.  But there was something my inflated ego couldn’t hide: a lack of results.

Back in my early college years, I thought I had my head wrapped around increasing vertical jump.  I’d tell everyone, even people who didn’t care one bit about jumping higher – lifting heavy weights makes you big and slow, you need to train explosively.  They agreed – it made a lot of sense.  I felt I was headed down the right path – that someday I’d be dunking a basketball.

I spent summers in my parents’ basement, training twice a day, 6 days per week.  Tons of plyometrics, light weights, everything as fast as possible.  But nothing happened.  I still wasn’t dunking.  My standing vertical stayed in the low-20s, my change of direction and sprint speed was pitiful, I was developing “jumper’s knee”, and I looked like I had never touched a weight in my life.

This lead to a critical realization.  Maybe I was wrong.  Maybe I was missing something.  It took about 5 years until I saw the elephant in the room: I was weak.  And weak athletes do not jump high, strong athletes do.

Study #1: When weak athletes were put on two different training programs – one group strength and the other power – the strength group got stronger and increased jump performance better than power training did [5].

Takeaway:  If you are weak, strength training can make you jump higher and increase strength better than power training.

Study #2: When put on ballistic (explosive) training, stronger individuals had more benefit in jump performance than weaker individuals [6].

Takeaway: The stronger you are, the more effective explosive training can be.

Study #3: Only strong individuals (back squat > 2.0 x body mass) showed a potentiation effect of power and velocity on horizontal jumps after an ascending back squat protocol [17].

Takeaway: The stronger you are, the more beneficial strength-power complexes are to jumping ability.  Example strength-power complex: Heavy set of back squats paired with box jumps.

The same is seen across the literature: Increased strength levels are correlated with jumping ability [10, 11, 14, 16, 19, & 21].  A stronger bench press [10, 14] and a stronger back squat [14, 16, & 21] are related to a higher vertical jump.  In all likelihood, if you simply get stronger, you will jump higher.

Basic Physics

Newton’s 2nd Law of Motion states: The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.

When you jump, sprint, or change direction; you must apply force into the ground to accelerate.  Same goes for swinging, throwing, or tackling; except the force must be applied to the object.  The more force you can apply, the greater the acceleration.

Newton’s 2nd Law to solve for acceleration is: Acceleration = Force/Mass

More force means more acceleration and more mass means less acceleration.

In terms of mass, this is why when an athlete loses a few pounds of body weight, they seem to be quicker on their feet.  And why acceleration comes easier for lighter, smaller athletes than it does for heavier, bigger athletes.  It also explains why it’s easier to swing a lighter bat, wear lighter equipment, throw a lighter ball, and tackle a smaller opponent.  In these cases, less force is required to produce similar acceleration.

So, aside from cutting body weight or playing with lighter equipment, the only other option to increase acceleration is through producing more force.

Stronger athletes apply more force faster than weak athletes [11].  More force means more acceleration – stronger athletes are able to change speed quicker than weaker athletes.  But why is it that stronger athletes are able to apply greater force in the first place?

Because strength is the ability to produce force.  If you increase strength, you increase your ability to produce force, which transfers to increased acceleration.  Acceleration affects velocity because Velocity = Acceleration (Distance) x Time.  And since velocity is speed (in a given direction), this can be extrapolated to mean faster speeds come from higher forces.

Jumping, sprinting, cutting, hitting, throwing, and the speed of all other athletic movements are improved when more force is applied.

More strength = more force = more acceleration = more velocity

When you’re weak, heavy lifting does not make you “big and slow”, it makes you explosive and fast.

Maximum force is required to be fast in any sports movement [13].  The stronger the athlete, the faster they can perform these given movements [22].  This is because capacity for speed is dependent on level of strength [3].  And when matched for body weight, stronger athletes perform better in explosive performance measures than their weaker counterparts [16].

Strength and Athletic Performance

Sprinting.  In short-distance sprints, faster athletes are stronger in the back squat [1, 4, 7, 8, 14, 16, 18, & 21].  The same is true for tests of agility, sprint acceleration, and sprint velocity [16].  Stronger athletes are faster.

Velocity.  In Division 1 collegiate volleyball players, shoulder extension strength at high speed is highly related to spiking speed [9].

Levels of Sport.  Stronger athletes are seen at increasing levels of sport [1, 2, 10, 12, & 14].  This is true for rugby [1 & 12], collegiate American football [2 & 10], and ice hockey [14].  When comparing professional to non-professional, higher divisions to lower divisions of college play, and elite to junior elite status, the stronger athletes are found at higher levels of competition.

Power output.  High power athletes do more work in less time.  This also happens to be what makes them explosive.  Stronger athletes produce more power [1, 11, 12, 14-16, 19, & 20]. Power outputs at light and heavy resistances [15, 19] and with weighted and un-weighted jumps [15] as well as tests of power such as: power cleans [10], bench press throws [1], jumping, throwing, and changing direction [11], and weightlifting performance [20] are all improved with increased strength.

The Paradox

For weak athletes:  Training explosively is not the best way to get explosive.  You must be strong first.  Somewhere around a 2 x body weight squat [17] (or similar measure) will provide you a solid base of strength that can 1) increase explosiveness and 2) enhance the effect of explosive training.  Focus on getting strong – it’s one of the primary factors in becoming a beast.

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In 5 weeks, my back squat has increased 60 lbs., deadlift up 65 lbs., and bench press up 40 lbs. since starting the Hypertrophy Cluster Protocol

Peter A. - Former Collegiate Baseball Player



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