The wind sprints workout is a very effective interval training workout for building running speed, but needs to be approached with care.
I've seen a lot of people talk about sprinting and it's a subject I've stayed away from wherever possible because it's fraught with danger. The risk to reward ratio leans heavily towards the risk side of the equation, especially as we get older.
I'm astounded by the number of respected coaches and trainers who will happily prescribe sprinting to someone who hasn't exercised for years because "HIIT is more effective than steady state cardio (LISS)".
This is wrong on so many levels.
First of all, HIIT isn't actually more effective than LISS for a host of reasons, not least among them the fact that the average person cannot achieve anywhere near the intensities that are used in most studies.
HIIT (especially those featuring sprinting) also carries a disproportionate risk of injury for someone who is overweight and de-conditioned. If you want to hurt someone who is carrying 50+ pounds of excess body fat, get them to sprint a couple of times a week; they'll injure a tendon soon enough. That's if they don't have a cardiac event first!
Having said that (because I really have to say it, both professionally and ethically), a short block of sprinting can be beneficial assuming you have the underlying running conditioning to support it. That's where this wind sprints workout comes in.
A few things to note:
You MUST warm up thoroughly. This means gradually increasing intensity, range of movement etc. If you want to hurt yourself, skip the warm-up.
Sprints are short; 40-50m. For most people, that's 6-8 seconds running. Once you get beyond that as recreational athlete, you're not sprinting any more.
Recoveries are quite long, typically 2-3 minutes or more. If you're putting in a true maximum effort, you need time to recover if you're going to do the next sprint justice.
Less is more. You're better off doing a wind sprints workout that has 4 great efforts than 10 mediocre ones.
The goal is to be fast and fairly effortless throughout, not to be exhausted at the end.
How to do it...
Do this workout once per week MAXIMUM.
Find an area that is flat or slopes slightly uphill, with a good surface (no holes, soft patches etc.) and measure a distance of between 40 and 60m depending on how fast you can sprint, with 20m of runoff distance afterwards. You want 6 to 8 seconds of sprinting maximum.
Do a thorough dynamic mobility warm up for at least 10 minutes, 20 would be even better.
Start in your stance of choice (I like a three-point stance, but one foot forward ready to run will do).
Sprint from the start to your marked point as hard as you can (accelerate up to speed, pump the arms, focus on being relaxed and driving forward). When you reach the finish, DON'T stop on a dime, let yourself cruise to a stop over the next 20m or so.
Walk back slowly, do some dynamic mobility exercises and breathe for 2 to 3 minutes (you'll get to know when you've recovered).
Repeat between 4 and 10 times, stopping when you're no longer able to give it 100%.
Do a thorough cool down, focusing on your key mobility issues.