I think one of the biggest misunderstood parts of sprinting is the spine position during the start. With most people focused on the athletes staying lower and therefore negatively impacting the ability of the athlete to effectively get through their start and drive phases. In this post I will show you what you want to be doing out of the start.
Spine position is important for maximizing your speed and force while running. In the beginning of a sprint, it is especially important to have efficient force application, as it will set you up for the rest of the run. Commonly, people begin their sprint by kicking their feet too far back, practically kicking their butts, which makes it so they get too vertical too quickly. (Notice difference of swing leg of the athletes below)
By doing this, you spend too much time on the ground per step, which makes it harder to properly transition from the start phase of your sprint to the drive phase. The first three steps are the most crucial, and over time, you will begin to develop a rhythm that will help you seamlessly transition from the start phase to the drive phase. The main goals during your start are to get your hips through, get your spine through, and maintain a high position within your heel during foot contact. (Notice the difference in heel heights as well as the position of the hip compared to the foot below)
In order to really drive your hips forward, you really want to drive your front knee forward. As you drive that knee forward, it makes it so you can roll your hips forward more, and as your hips roll forward, your spine will follow as well. Your first motion needs to have a lot of force that will help with driving your front knee forward. Meaning strong extension with the hip and flexion/extension of the arm and shoulders. (Reference Usain Bolt above). The main goal of the start is to build quickness and correct ground force. The distance per step comes from hitting the ground horizontally, NOT vertically. (Notice below the foot is out in front of the hip, but behind the knee then pulls back underneath.)
When it comes to the start, the important thing is repetition. The more reps you have the better you will be. This should give you some good visualization of what can be done in order to improve your performance. You can check out the video on this here as well as check out our 3 month speed program with personalized breakdowns below.