Tuesday, January 8, 2013

Box Jumps – Why Do We Do Them?


I find that the box jump is one of the more misunderstood exercises out there.  In the past, I have myself questioned what their purpose is, and have heard multiple other coaches question them as well.  Yet, I have stumbled across only one article from a well known coach on box jumps that was negatively biased, and was focused solely on how dangerous they are.  There was no mention of the benefits of box jumps.  This brief article is meant to shed some light onto why you would want to use box jumps, when they will be no different than squat jumps, as well as safety measures to protect you and your athletes from injury. 

When to Use Box Jumps

As with all exercises and tools (barbell, kettlebell, dumbbell, etc.), it is important to first determine what it is you are trying to accomplish, and then decide what the best course of action will be to achieve this goal.  Let’s break box jumps into two separate categories: single effort box jumps, and continuous box jumps (performed as a plyometric w/ minimal ground contact time) 

Here are some reasons to utilize single effort box jumps in your routine:

·         You are injured and must avoid the ground reaction forces associated with landing

·         You are managing fatigue/avoiding overtraining and, again, must avoid landing

·         Box Jumps can be more dynamic than a squat jump, as they require the athlete to explosively flex at the hips in order to safely land on top of the box

·         You plan on standing up on top of the box and dropping off to land, thus better developing your ability to decelerate when compared to simply landing from the height your legs attain in a squat jump

·         It presents a challenge for the athlete, with new visible goals (higher box) to complete

·         They are fun, are a good way of turning training into a competition amongst the athletes, and creating interest and passion for training

Here are some reasons to utilize continuous box jumps in your routine:

·         You need to develop reactive strength in your athletes.  Reactive strength is a form of explosive strength, and refers to the ability to get off the ground as fast as possible once making contact with it.  This means that the exercise is performed as a plyometric, with only the balls of the feet making contact with the floor, aiming to get back off the ground as fast as possible.  Please see this article on explosive training to learn the various derivatives of explosive strength.

·         You don’t have enough equipment or space to perform multiple depth jumps with multiple boxes.  Continuous box jumps are really the same thing as depth jumps, except you will only be able to use one box height per set 
  

How is the Single Effort Box Jump Different than a Squat Jump?

One question posed recently by my friend and fellow strength coach, Dan Adams, and one that myself, and I am positive many others have, is why not just use squat jumps with healthy athletes?  Dan and I discussed this in depth, and determined there are multiple variables that must be considered to differentiate the two. 

                If we are talking about single effort box jumps, we must consider many variables, one of which is Center of Mass.  When you perform a squat jump, and when you land in an athletic ready position on top of a box during a box jump, your center of mass is actually the same as if you were performing a squat jump.  Therefore, unless you are going to stand up on top of the box, and then step off and land, the force your body must absorb upon landing is the same no matter if you are performing a basic squat jump, or if you are jumping up onto a box and lightly frog hopping off the box to get back to the ground.  Thus, if you are looking for greater ground impact to develop the athletes’ ability to decelerate, make sure they stand up on top of the box prior to jumping back to the ground.      

                A single effort box jump is a great exercise for those who are rehabbing, or are monitoring fatigue levels, and should not be exposing themselves to a high degree of ground impact.  However in the case of the injured or over-trained/over-reached athlete, you should have your athlete jump onto the box, and use a chair or other device to step down safely to the floor.

                Box jumps are fun and challenging!  It is easier for an athlete to give full effort when they have no choice but to get on top of the box, or miss it and topple over the boxes or scrape their shins (see safety measures below!).  Starting a competition amongst a particular group of athletes can also be a good bonding experience, as well as generate excitement and passion for training. 

How is the Continuous Box Jump similar to a Tuck Jump?

                To realize the similarities between a continuous box jump and a tuck jump (both performed as a plyometric), it is only necessary to remember the Center of Mass variable.  In the continuous box jump, the athlete jumps up onto a box, very quickly jumps back down on the same side, and makes contact with the ground with the intention to explode back up off the ground as fast as possible.  In the tuck jump, the athlete explodes off the ground, tucks their knees a high as possible to their chest, and then explosively drives their feet into the ground upon landing in order to get off the ground as fast as possible.  In both exercises, the center of mass stays the same; therefore eliminating any extra benefit from ground impact forces you may believe you are increasing/decreasing by adding/eliminating the box.  In order to increase the ground reaction force upon ground impact, you will have to, again, first stand up on the box prior to stepping off, or begin a depth jump from a greater height. 

Safety Measures

It is very common to see pictures posted on social media of those who have attempted and failed a box jump.  In order to save the skin on your shins when failing an attempt on a wooden box, or avoid painfully collapsing on the floor, it is necessary to seriously consider some safety precautions.

·         Use foam/padded plyometric boxes if available

·         Have a spotter behind the athlete, in front on the other side of the box, and on both the right and left of the athlete.  This creates a safer environment, and also helps mentally prepare the athlete to jump to a high box.    

·         If you are using aerobic steppers, or multiple smaller boxes as your platform, ensure that the spotters are holding the box steady as you start getting to the greater heights. 

·         If you are monitoring fatigue, or are dealing with a rehabbing athlete, have them step down safely off the box.

·         Unless you are attempting a personal record box jump, make sure the athlete lands in an athletic ready position with a neutral spine. 


1 comment:

  1. Thanks for such detailed information regarding box jump.I just came to know that I was also doing it wrongly since ages. Thanks for the correction.

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