Hi everyone, it’s been a while since I’ve put out a written piece. I’ve wanted to find a platform to regularly put what’s on my mind out into the universe as it helps consolidate my learnings; and sometimes people enjoy some of these reflections for themselves. Despite being an instagram addict, I don’t have any skills with content creation and anything that I have ever put out via instagram reflects such a small percentage of the thought and understanding on the topic that it feels like anything made on instagram is underselling the topic. I was also thinking about the possibility of starting a podcast; but it’s a saturated medium and I think that talking, compared to writing, is a very passive form of communication (I guess this is called yapping). So, I’ve landed on trying to create a written piece on a semi-regular occasion for those who’d like to learn more about coaching and more specifically, speed and power development. This will be just a lunch time effort on a Friday, so wish me luck.
The first written piece is about The Block Start - I thought I’d use this to overcome writing inertia and get the ball rolling for this writing endeavour.
The block start is an integral component of every sprint race from 100m - 400m. The block start, along with the initial few steps of any race, reflect the greatest changes in acceleration of an athlete and therefore, the performance of the blockstart and the subsequent 2-3 steps represent a great opportunity to positively influence the outcome of any race. The block start and the next 2-3 strides (lets just call this ‘early acceleration - the moments in which an athletes primary objective is to overcome inertia) have a greatly different profile to the strides experienced at maximal velocity sprinting and thus, the strides of early acceleration should be acknowledged as a possessing different biomotor skills to that of maximal velocity sprinting. Roughly 60% of horizontal velocity can be accomplished at the clearance of the blocks; by 20m most athletes are close to around 90% of maximal velocity.. With this in mind, it should be evident that if you are training a sprinter, significant time needs to be dedicated to the block start if you are to expect transfer from training to the competitive environment. I won’t really be talking about the methods or sessions I use for block starts, but I thought that it was important to highlight that this is something coaches need to target for most of the year in order to see improvement.
The kinetic problem
Before getting into the technical aspects of the block start, I think it’s important to understand the kinetic demands of this part of the race. For most sporting activities, I like to do this first - understand the kinetic problem and then solve it through an efficient kinematic model.
The athlete needs to apply force into the blocks from both front and rear legs in order to propel the body forward. The body is completely stationary in the set position, so the velocity of the athlete is 0m/s - and by pushing into the blocks, the athlete will overcome inertia and begin accelerating.
The athlete needs to apply force in a horizontal force vector in order to generate horizontal velocity.
The athlete needs to apply force in a vertical force vector in order to raise the centre of mass, to overcome gravity and to counteract rotation.
The outcome of the athlete’s efforts in the blocks will be determined mostly by:
The set up of the block start
The skill of the athlete
The physiological abilities of the athlete (mostly rate of force development).
Already the word force has popped up a few times, and at least in my case, when I first started to imagine how force manifests when looking at someone sprint, I always correlated it with high strain and high magnitude force application efforts, e.g. someone who could squat or deadlift heavy is good at producing force. This thought process was partially true - as athletes who can squat well are good at applying force, although the time frames at which sprinting occurs, even when coming out blocks, determines that the rate of which force is applied is extremely high. Elite block starters are exiting the blocks at 280 - 350ms, with myself exiting the blocks in roughly 400ms. Therefore, when it comes to discussions of force within the context of the blocks, and sprinting in general, it should be noted that success will be found if athletes are able to apply forces at high rates and in the right direction. In this instance, you’d rather an accurate pistol over a misguided cannon.
As I mentioned earlier, I won’t be going into methods or session organisation for block starts in this article (because I want to try and keep it as a lunch time effort). But, with the above information about block exit being 280-400ms, it should further highlight how S&C interventions can have great transfer to this part of the race. I’d recommend that in the gym, you train the athlete to powerfully overcome inertia within those time frames - basic exercises such as squats, deadlifts, step ups and olympic lifting variations can be manipulated to be performed within those time frames and becoming proficient in these exercises will have great transfer to block clearance.
The Set Up
Above is a picture of a block setting for one of our short / pro sprinters. The framework for which I use to start setting up someone in blocks is taken from Ralph Mann’s ‘The Mechanics of Sprinting and Hurdling’ and then tinkered according to a multitude of factors (flexibility, strength, skill, injury history perhaps). For the most part, block settings should mostly be determined by anthropometry - which is why Ralph’s recommendations for the front block to be placed:
Front leg: Place your knee on the ground 3cm behind the starting line and place the front block here.
Rear leg: Measure the distance from the front block to the starting line, and then 1.7X that distance for the rear leg.
When I adopted this position, it felt much tighter in the front leg, and longer in the back leg; but the results have been very good for our squad as you’re put into a position which allows for both effective generation of horizontal velocity, as well as being able to transition out of the early acceleration phase into late acceleration/maximal velocity phases.
Some simple heuristics I’ll look at are:
Parallel shin angles
~25 Degrees negative torso angle
Shoulders slightly over start line
Relaxed neck (if anything, slightly tucked).
Execution
We’ve identified that for block clearance, we need to put force into the blocks. Parallel shin angles allow for contributions of both legs in the pushing action; and allow for the athlete to smoothly transition from block clearance into a regular running gait. Early acceleration requires proportionally higher horizontal force in order to horizontally displace the body; as such, as the athlete exits the blocks, the athlete should extend the knees and then the hips in order to move forward and not in an excessively vertical manner.
Vertical forces are required to shift the centre of mass vertically and overcome gravity, and as such, as the athlete exits the blocks, there will be a rise in the torso angle of the athlete. In the past, in the pursuit of organising all forces horizontally, I would organise a relatively flat torso angle in the set position thinking that I would be able to exit the blocks at that same angle. This typically leg to the torso angle shifting upwards as I exited the blocks, leading to excessive flight time for stride 1 and this had negative cascading consequences for the rest of the race.
In regards to torso angle, I’ve found more often than not setting up athletes with a slight round in their thoracic; and flexion of the neck, accompanied with a subtle posterior tilt of the pelvis. The goal of this is to inhibit excessive recruitment of the spinal erectors; which pulls the athletes upwards into the air and has a negative effect on the pelvic position of the athlete - which cannot really be recovered at other parts of the race. The subtle posterior tilt tries to organise the athlete to have worse leverage for proximal hamstrings as ‘pushers’ into the block and more towards quads and glutes. The parallels I draw for this phenomena are rounding the upper back slightly during a 45 degree back extension; and maintaining this upper back position as the athlete extends their hips.
In order to be reactive out of the block setting position, the athlete needs to create tension in the system prior to the gun going off. This is like when a dog gets the ‘zoomies’ - they hold a static position with high tension to then bolt off as quick as possible. Pretension isn’t just about getting tight and stressed while in the set position. Tension is created by:
Pressuring the blocks in the set position
Offsetting this horizontal force in the blocks by working the shoulders in the opposite direction
The slight posterior pelvic tilt and a slight thoracic curve will engage the rectus abdominis and a moderate inhale will engage the obliques.
This pressure system is also exacerbated by putting the agonist muscles on stretch (glutes and adductors through hip flexion; quadriceps in knee flexion and the back musculature in slight flexion). Hopefully, if the athlete has undergone the appropriate training modalities, they’ll be able to utilise the stretch of these tissues to create greater accelerative outputs as they exit the blocks.
Pretension should guide effective horizontal displacement of the athlete out of the blocks rapidly. The fingers will be removed from the ground and with the intention to press into the blocks already engaged, the athlete will move forward. If the athlete is able to do this, it will cause a reaction which encourages the athlete to reactively flex the hip to bring the femur through for the first step; prior to the flexion of the knee on the same leg. This athlete will hopefully maintain a low heel position as the femur swings through; which will lead to both low flight time (you can only get faster on the ground) and put the thigh in great position of leverage to extend the hip back into the ground (negative foot speed).
The femur will also swing through more efficiently out of block clearance if they’re able to maintain some degree of dorsi flexion as the athlete exits the blocks. Excessive plantar flexion at block clearance will slow the action down and also inhibit tension on the anterior chain; creating poor leverage for the hip flexors. Although the plantar flexors, particularly the gastrocs, contribute to an increase in propulsion at the final portion of the stride, it slows down the action and this creates issues for subsequent strides. I liken this to a ‘follow through’ action in sports - i.e. kicking, shooting a basketball, a golf swing: it’s a natural and beneficial action in these sports but following those sporting actions, there’s no follow up action (no cycling into the next stride, next swing, next shot, etc.). So in this context, the additional benefit of plantar flexion is lost due to the detrimental impact it has on the subsequent stride - sorry to those with a pretty, idyllic block start… it might just be slow.
(me doing a drill with an athlete trying to encourage low heel recovery - which in turn, maintains dorsi-flexed foot posture)
Wrapping up
Block start performance is a multifactorial phenomena and therefore, many variables need to be considered to evaluate how to improve performance. My parting pieces of advice are to:
Athlete’s need to be beastly and powerful to overcome inertia. With this in mind, youth athletes; and even many female athletes in their teens, will often have a really bad block start so don’t expect them to look like Christian Coleman or Ewa Swoboda when they just don’t have the horsepower to do so. Strength train intelligently and you’ll see the technical model improve almost automatically.
You should consider periodising your block start training. The position of the block start itself is cramped and hard to get out of; and at least for my own athletes, I like to have a progression model for start positions of: standing -> 3-point -> crouch -> blocks. We are in blocks in late GPP phase.
As much as the block start is important, the performance of the block start cannot be measured in isolation. The block start will influence the performance of the first and second strides; so if you’re faceplanting and are slow in those strides, even if you’ve got the jump on your competitors out the blocks, you’ve failed the block start. If you’ve taken too aggressive of an angle out of the blocks and are unable to transition gradually through the postures of acceleration, you’ve also failed the block start. Acceleration, in a general sense, should sequence effectively and have each stride contribute positively to velocity.
Block starts need to be trained in both isolation and within competition at training. Everyone looks good running solo, so the technical model needs to be tested under the stress of pressure.
Good luck in your training and reach out if you have any questions about points discussed in this article.
Cheers,
Jack
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