Two Determinants of Speed
One of my big pet peeves is when I hear people talking about speed and the conversation typically starts with ‘there are two ways to improve speed: stride length and stride frequency’. The thing that bothers me the most is that these aren’t truly determinants, but simply characteristics. If you take an athlete out onto the track and ask them to increase their frequency or increase their stride length, do you expect to get immediate improvements? Mathematically you can describe the results of a 100m sprint through these two variables but it doesn’t give us much to go on as coaches. Whether looking at linear speed or change of direction speed (COD for our purposes) there are really just two determinants. These are OUTPUT and POSITION.
OUTPUT This is the favourite of the strength and conditioning coach because it is more or less the horsepower that the athlete has. Two of the more important outputs are overall force production (strength) and rate of force development. Each one of these can have a major impact on stride length and stride frequency. If you produce more ground reaction force than you can probably create a longer stride. If you can reach that max force quicker, you can spend less time on the ground and thus stride more frequently. So for the intent of improving speed or COD our output becomes a very trainable factor. With the right tests, we can easily monitor how well we are able to change these. Using force plates you can look at countermovement jump data, maximum force production through an isometric mid-thigh pull, or look at different aspects of the profile during a weightlifting movement like the snatch or clean. Tracking things like maximal force and rate of force development (and if you wanted, the marriage of the two via power measures) can tell you exactly how much your outputs have changed. We know if all else is equal, improving these outputs should improve speed and COD. Unfortunately, this isn’t always the case, and that brings us to our second determinant.
POSITION This is the second major determinant and just as important as the first. Position can be thought of as the skill component or technique of a given task. Let’s think about sprinters for example. We have seen sprinters that look absolutely perfect when they run but don’t win…we have also see some that run ‘crazy’ with limbs flying around still end up on a podium. Then the world record holders seem to have the best of both worlds. The runner with technique who doesn’t win is likely lacking in output, while the runner who looks lost but does well is producing plenty of output but in the wrong position. The same thing can be noticed in the sport of weightlifting. The snatch, or clean and jerk, are both very technical lifts. At the same time, they are still very different from darts or golf in that they require the most weight to be lifted as possible. With this combination you see the interplay of output and position displayed very strongly. It is believed that the chinese lifters are currently the best because their technique (position) is almost flawless, so they can complete lifts to the absolute maximum of their output. Some other countries use different methods, and although they get lifters very strong, possibly stronger, they cannot complete lifts as close to their maximum output levels, making their totals lower. So how does position come into play for a strength and conditioning coach? Well, it really depends on the situation you have and the time you have with your athletes. At FITS we prefer the term athletic develoment specialist for a few reasons. First, we are about all-around athleticism so we want out job description to reflect that. The second part is that we truly embrace the term development when it comes to our athletes. We understand that for every bit of output you add in the gym, position needs to be taught and solidified on the court, field, ice, or snow. When a field sport athlete wants to get faster, building output is definitely a great place to start. Once a sufficient amount of strength and RFD has been developed it is important that it is utilized in a way that maximizes speed in the appropriate direction. This means force application has to be as efficient as possible, and this is dictated by angles. Angles of joint position, body lean, and foot strike. At FITS, we use a variety of tools to ensure we are coaching athletes to be better, not just stronger. We have a comprehensive approach to development that is second to none and I am so proud to be part of the team!