Its good as a learning tool, but I wouldn’t do the same pattern for too long. The danger is that these “segments” will become ingrained.
I think the learning use of the Mach drills diminishes in more advanced athletes, but they are still a good thing to do as part of the warm up and as an observation tool for the coach.
I think the technique runs that you describe are very useful, but should probably follow the drills and precede the maximal stuff.
BUT… change them around! 
dcw23,
When you said ingrained that got me thinking about what Charlie wrote in speed trap about Ben doing ins & outs for years so that when he raced he went into overdrive at 20m. When watching his races and practice starts on video I see a noticable pick-up in acceleration at 20m and was wondering if someone would benefit by doing 15m acc. 20m hard, 20m easy therefore, hitting that overdrive phase 5 m sooner.
Charlie,
Is 20m acc. (or longer) for ins & outs the norm? Is 15m or even 10m acc. for ins & outs done at times? If so, what part of the year?
-Balance
I think ins and outs are a fantastic tool. What Charlie describes is different though. Probably something along the lines of Accel - turnover - accel which will allow the development of acceleration from a higher initial speed, i.e. layering acceleration on acceleration but not falling over yourself while doing it - does that make sense?
What I was referring to is that if this 25/20/20 is used every single workout, it can become so ingrained that the athlete will auto switch to speed mechanics at 25m, and may end up doing this in a race and its sort of like throwing out a parachute. Its hard to notice in practice but quite dramatic in competition.
dcw23,
It makes good sense. Thanks for clearing that up for me.
-Balance
Balance
We did do a lot of in-and-outs, but remember there is a BIG CNS cost to speed change drills so we tended to drop them close in to meets, particularly outdoors. While the 20-20-20 drills did influence Ben’s pick-up in actual races, it happened EARLY in the race- not much past 5 or 6 meters, because, at full blast from the blocks, he’d reach the speed where the drill kicked in that much sooner. As a rule, you need a fair bit of time with drills, as you can perfect your technique over the required number of repetitions with far less energy cost.
Charlie,
I was thinking about the use of I/O’s not for different emphasis of speed but at submaximal speeds to emphasise an aspect of sprinting technique, e.g. stepping over. You have mentioned the use of sub-maximal fyling 20’s for this exact purpose. Any merit?
How much were speed change drills done during the indoor season?
You can do more in the indoor season as there is usually less conflict with SE, which is emphasized later.
I would assume these were done earlier in the work week and early during the indoor season to allow for tapering?
Generally, there is a conflict in the simultaneous development of top speed and SE as the main focus of a training phase. As a top speed drill, is this the reason you see a conflict between in and outs and SE? I.e., is it a “top speed vs. SE” thing or some other reason?
On another tangent, would you use longer than 20 - 30 m in and outs as an introduction to or a variation of SE workouts? I know you probably don’t prefer this approach, but in what case would you recommend the use of it, if any? Thanks!
A happy new year to you all guys!
No, i prefer to keep this as alactic work.
Sorry, I was referring more to FEF(/EFE) drills of longer durations, say 40-40-40 or 50-50-50, to work on specific race parts perhaps. I.e., not as a top speed drill. You opinion on this, please?
I would do 50F, 50E, 50F at times. these are often called “hollow 150s” and were often used by Alan Wells and later by Dan Pfaff.
Hi Charlie (or anyone)
What would be the purpose of these? Speed endurance work toward later intensification i.e. 50f-50e-50f moving toward 150 all-out, or a means of reducing intensity on a down woeek from the usual 2x150@100% for SE?
To move towards a longer drill may be one reason, yes and/or to work on specific parts of someone’s training may be another. Not sure I would use them in an unloading week (they can be quite stressful) and/or much later in the season (you need to put it altogether at some point). It’s always a combination of intensity and volume anyway, of course. Others?
PS by “…100% for SE” do you mean effort-wise?
Yes. Both effort and hopefully when ready time also.
As Charlie would say, I would go with time rather than effort -which is subjective- and trying not to mention the 100% to your athlete.
Thanks Nikoluski
I’m reasonably certain, Wells would have gone 50/20/50.
Fast for the first 50m - ease off as going through the tape or coast for 20m, then hard for another 50m.
This is a ‘stock’ session Wells would have adopted from his coach Wilson Young.
A normal session woul be 6 x 50/20/50 in two sets of 3. Walk back between reps and 10 min rest between sets.
During the specific prep phase we would start with 6 and over several weeks work up to 12 (2 sets of 6).
These would be flat out from blocks with a gun or whistle start. Tough session but the athletes if conditioned properly over the previous months, should be able to handle it.
I’m sure you’re better informed on this than me.
50/20/50 then.