The classic float and sprint option of alternating sprinting and relaxing in repeated zones is a popular option for developing maximal speed. Ins and outs or whatever people wish to call it seems to be a method that people do, but don’t share why. Often during visits I see it done and it’s poorly executed, meaning the sprinter was sprinting at the wrong time or a mechanical issue existed. Sometimes I have seen really good execution and could see why the coach chose the option. Like the discussion before regarding general maximal speed work, I will get into the more demanding option than the classic 30 fly, the Sprint/Float/Sprint option done everywhere.
Distances and Zones- One question I have is how do coaches think the athletes are perceiving the delineation of zones with a haphazard or carefully placed orange cone? When athletes accelerate to a speed zone and shift into float and back into sprinting, the transition is not instant, so why not add 5 meters or more so the athlete has some time to get into gear. I have never seen people pull, but I am sure people have pulled going from relaxed float into a sprint, how are people suppose to transition. A flip of a switch or few steps? I like using tennis balls cut in half (Gary W!) and have that be the reaccelerating zone and a tall cone be the shift into neutral marker. I prefer Sprint-Neutral-Transition-Sprint as it seems to keep guys from getting excessively sore the next day. Breaking rhythm or reestablishing rhythm is hard work both skill wise and on the body.
What are we Training?-Are we training the relaxation from the supported sprint or are we doing cluster sprints, meaning we can hold top speed very long and need a way to micro rest? I never got a good answer when I was going through formal education. Some say both but does one need to pair it together? How do we time this properly? Do we time it? How do we evaluate the loading one gets as it’s not something we can simply add distance and average the speed of the contrasting velocities. What is the mechanism of adaptation? How do we know it’s working? Why is it better than a traditional fly?
My Observation- I have only done this sprint and float option a few times and found it was an artificial trick to do more speed work and challenge advanced athletes. I have timed the segments of well executed zones and didn’t see anything impressive but the ability to keep a high speed extended three consecutive (alternating) zones without much decay if any. I like to compare top performance of one of the zones to all-time fly performance. I like to see no drop off between float runs and a 1-2% difference between all time best fly sprints. The neutral or relaxed float time tends to be about 10% slower, but I don’t know if that is just happenstance with me or something repeated. I don not state that this is a suggestion or even ideal, just an observation.
Decay Rules- I see a lot of discussion about monitoring fatigue by a few pundits and wannabe gurus, and suggesting that a magical 7% drop off is ok is a flagrant attempt to create expertise when in reality it’s clear that it never happens in real life. Using electronic timing and video chronometers, I have never followed a drop off based on the 10% rule or similar. What is one comparing to? All time best splits? Someone early in the GPP would stop before they even start because they are nowhere near PB levels. Also you can only be at PB levels a few times a year. The % drop off is like a sniper shooting from boat during a storm, an impressive shot to talk about but who is doing it? Decay must be based on experience of working with volumes and clear communication about each rep.
Pulse Train Envelope- One Francis inspired theory is that alternating pulses create a threat removal in order to remove co-contraction. Like the neurological window after loaded sleds during contrast training, this method may break through speed barriers or stereotypes since they act similarly to wind assisted runs. I am seeing some interesting EMS protocols in Germany and Italy with some training camps that are often examples of low tech training with grass runs being a red herring. Contrast work may spark changes, I have no research yet as the motor skill and sprint adaptions physiologically are not often studied.
In summary, the alternating float and sprint option challenges the athlete to be able to switch rhythms and I think it has merit, how we execute it with distances and equipment set-up isn’t clear yet, but I expect coaches and athletes to share their experiences so we can start drilling down why it remains popular. I like the sprint/float/sprint to be repeated only up three sprints of distances between 20-30 meters. This will sometimes require an acceleration off the curve for the longer option.