What can we learn about an athlete from a vertical jump test? The first thought that may have jumped in your mind is “explosiveness” or more specifically, “lower body power”. This is a correct answer. However, this is only one of a variety of pieces of information that a coach can garner from a simple jump test. The rest of this article will discuss some other useful takeaways we can get from jump testing our athletes.
Reactive ability is arguably one of the most important physical qualities that an athlete can possess. This refers to the stretch reflex that results from a rapid pre-stretch of a muscle that s enhances the subsequent concentric contraction. This type of action occurs during rapid change of direction, sprinting and of course, jumping. A simple test of an athlete’s reactive ability is to have them perform a vertical jump with a counter-movement and one without a counter-movement (i.e., a squat jump). In the first situation the athlete is able to take advantage of a rapid stretch reflex by performing the counter-movement (i.e., rapid flexion at the hip and knee and throwing down of the arms). In the squat jump, the athlete will flex at the hip and knee and pause thereby eliminating the effect of the stretch reflex. Highly reactive athletes will have a much higher counter-movement jump than squat jump. Players showing a poor counter-movement jump compared to the squat jump would benefit from plyometric training. Therefore, this assessment is a great way to drive program design based on the needs of the athlete.
Fatigue, Pain or Loss of Strength/Power
Tracking vertical jump performance throughout the competitive season (i.e., once per week) can be very insightful regarding the training status of your athletes. Suppose an athletes jump scores are showing a progressive decrease week-to-week. This can indicate that the athlete is accumulating fatigue which we know can mask fitness/performance. Or it may be because the athlete is dealing with a nagging injury. This can be to the foot, ankle, knee, hip, lower back, etc. This would certainly require further investigation from the coach and athletic trainer to determine the appropriate course of action. Another potential reason for a progressive decrease in vertical jump performance is simply that the athlete is getting weaker. This is not uncommon during the competitive season where busy schedules and lots of travel get in the way of regular workouts. Therefore, when monitored over time, a simple jump test can provide a useful tool for evaluating training status and therefore enable better decision-making regarding programming.
An important thing to remember about the vertical jump test is that it is extremely easy to conduct. You can use a Vertec or a jump mat. Or if those are inaccessible, you can simply use a piece of chalk and measuring tape. Another great advantage to this test is that it is non-fatiguing which makes it convenient for routine monitoring that will not interfere with performance. Clearly, the vertical jump test can be a useful tool for more than just evaluating lower body power.