The so-called shuffle start has been making waves in the last few years, especially among elite circles [and most-especially in the United States]. It is characterized by a low projection angle from the blocks, an ultra-low heel recovery [often seen as a toe-drag], and a high step frequency.
This may be a controversial take, but I’ve long believed that this tactic is doing more harm than good, and is a perfect example of Goodhart’s Law.
Let me explain.
Firstly, you may be asking “what the heck is Goodhart’s Law”?
Well, Goodhart’s Law posits that “When a measure becomes a target, it ceases to be a good measure.” This principle, originating in economics, has broad applications across multiple disciplines, including sport and coaching.
For example, pacing is crucial in long-distance running. Runners often set split times for each mile or kilometer. However, if a runner becomes overly fixated on these splits, they might not adjust their pace based on the race’s dynamics, such as changes in elevation, weather conditions, competitor’s tactics, or their own physical state. By rigidly sticking to predetermined splits, they risk not capitalizing on segments where they could push harder, or not conserving energy when needed — potentially affecting their overall performance.
Similarly, consider the growing emphasis on individual player statistics in team sports, such as points in basketball, or goals in soccer. When these stats become the main focus, the broader objectives of the team may be compromised.
In sprinting, the primary objective of a 100m race is clear: finish the entire distance as quickly as possible. Yet, this straightforward goal can sometimes be clouded by a narrow focus on acceleration. It’s not uncommon for coaches and athletes to become preoccupied with early race benchmarks, such as the time taken to reach 10m, 30m, or even 60m, for example.
But as Coach Dan Pfaff often reminds us, “they don’t hand out medals at the 30m mark.”
While acceleration metrics are insightful, they need to be approached with caution. A hyper-focus on these early segments may inadvertently hinder an athlete’s overall 100m time. Even though the 100m isn’t about pacing per se, it doesn’t imply athletes should try to get to each point on the way to 100m as fast as possible.
Remember, the task at hand dictates the goal.
If the task is a fast 10m, then the shuffle start — with its lower projection angles, smaller flight times, and rapid step frequencies — may be an excellent tactic. But, if the task is 100m, it’s not so clear.
The shuffle start, or any strategy that focuses specifically on acceleration metrics, is a double-edged sword.
While it might offer an initial advantage, it almost certainly requires more work and places more musculoskeletal strain on the body — thus the potential knock-on effect of a lower maximum velocity later in the race.
And it’s later in the race that really matters.
Coach and sprint historian PJ Vazel’s study of 25 World and Olympic men’s 100-meter finals from 1972 to 2022 underscores this. In 24 of those races, the winner was the athlete who achieved the highest top speed. The data speaks for itself: top speed is king.
So does that mean we just shift our attention entirely from acceleration metrics to maximum velocity?
Well, not exactly.
As I wrote — the 100m isn’t a paced event. A sprinter doesn’t have time to gradually build up speed over the course of the race. It doesn’t matter how fast the sprinter’s maximum velocity is if they’re 3m back at 60m.
Instead, a fast 100m requires the sprinter to maximize their peak velocity, coupled with a start that is ‘good enough’.
But what is ‘good enough’?
Well, an alternative to the shuffle start is known as the ‘jump start’. It is marked by higher projection angles, longer steps, and a lower initial step frequency, compared to the shuffle. Coach Tom Tellez championed the jump start, and athletes like Carl Lewis and Leroy Burrell adopted it. Many of Coach Tellez’s mentees, including ALTIS Head Coach Dan Pfaff, also embraced it.
For the past four decades, the jump start has influenced how many coaches approach block clearance and early acceleration. It’s a bold, expansive start, with a more gradual build-up of speed, and theoretically will lead to a higher maximum velocity, and potentially a faster 100m time.
So is the jump start an example of a ‘good enough’ start? Should all athletes use this strategy? Well, not necessarily. While the jump start may lead to higher maximum velocity, if taken to its extreme, it may overly-negatively affect acceleration.
Reality is nuanced. It’s not a simple choice between the shuffle start or the jump start; there’s a spectrum, with the shuffle on one end and the jump on the other.
My role is to discern where each athlete naturally aligns on this spectrum.
Remember — how an athlete moves is governed by their unique physical attributes: their height, limb length, power, mobility, and coordination, to name a few.
To highlight the difference, let’s consider a 100m showdown between sprinters Zharnel Hughes and Christian Coleman [3rd and 5th in the 100m at the 2023 World Championships, respectively].
Coleman is much shorter, with rapid natural frequency — so he will gravitate towards a shuffle start. A ‘good enough’ start for him requires that he get to 60m really fast, and try to hang on as slower starters close in on him.
A good enough start for Hughes is very different though, isn’t it?
A shuffle start for Hughes would be costly, and almost certainly would hinder his top-end speed. A good enough start for him is one where he is within striking distance at 60m, allowing him to leverage his superior top speed and overtake Coleman before the finish line.
Like most things in sport, it’s complex, and contextual.
So the next time you’re tuning into a Diamond League 100m race, and the commentator mentions someone’s “bad start,” consider: How are they defining a ‘bad start’? Are they recognizing the context, or might they be succumbing to the pitfalls of Goodhart’s Law?