In Part 1 of this post I discussed the potential issues I saw with choosing a box height that was too low. The flip side to this is the less-common occurrence of choosing a box height that is too high.
First, how is the height of a box deemed "too high"?
When deciding how high to put a box for step-ups, I take into consideration how far the client can actively flex their hip and knee as well as dorsiflex their ankle. To find someone's active hip and knee flexion, I have them lie on a table or on the ground, preferably shoeless, and have them move the appropriate joint through the desired range of motion.
- Active Hip Flexion
- Active Knee Flexion
When they are no longer able to move it themselves, I record the degrees of range of motion achieved. This is their Active Range Of Motion (AROM) at that joint for that movement in that scenario. Then, I choose the height of the box such that the lesser of the three ranges is nearly maxed out when the client's foot is on top of the box.
What I mean is, my active hip flexion in the picture above is roughly 75 to 80 degrees, judging by the angle between the table and the anterior side of my thigh. My active knee flexion, however, is greater than that, judging by the angle between the line of my femur and my fibula.
(**Side note: This picture is demonstrating active knee flexion in a hip flexed position, which may be different for your client than active knee flexion with 0 degrees hip flexion as well as active knee flexion with hip extension. However, because the greatest amount of knee flexion in a step-up occurs in a hip flexed position, this is the position of choice for determining active knee flexion for this exercise.)
So, because I have less active hip flexion than active knee flexion, I will choose my box height based on the amount of hip flexion it puts me into relative to my maximum.
After that long-winded explanation, determining if a box is too high for a client is as simple as seeing if the box forces them into a range of motion at one or more joints that they would not actively be able to get to themselves.
The potential issue that arises with this is similar to my argument of stretching in that it is forcing the joint(s) into a range that the body is not actively allowing at that time. Doing so, as I have stated in the past, may decrease a muscle's ability to contract properly and generate force, which is not what you are wanting when you are trying to lift.
Problem 2: A box height that is too high forces joints into a range of motion in which the client cannot active get to themselves. This has the potential to decrease the contractile capability of the tissue around that joint.
Solution: Determine a client's active range of motion of the joints involved in the movement and choose the height of the box so as not to exceed this range.
In the final post of this series I will describe a technical issue that is often overlooked but makes a significant difference in the effectiveness of the step-up.
Charlie Cates, CSCS
Self Made®, Owner and Founder
Charlie Cates is a strength and conditioning specialist and the owner and founder of Self Made® (http://selfmadefitness.com/) in Chicago, IL. He has worked with competitive and everyday athletes of all ages and ability levels, from 9-year-old kids to NFL MVP’s. He can be reached via e-mail at charlie@selfmadefitness.com.
This article may be reproduced with biographical information intact.
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