Another fartlek workout particularly effective during base building is one where random pick-ups are tossed in throughout the run. The late ZAP Fitness founder Andy Palmer used to tell me to run 15 or 16 minutes worth of pick-ups during a long run; however, he gave me no details on the length of these pick-ups or the length and time of the recovery other than, "mix it up with some longer and shorter pieces." This is a truly "by feel" fartlek, and is a great one to execute as you are getting started.
After the requisite 6 to 14 weeks of standard base building, you should look toward your competitive season. With that change comes a change in the type of fartlek work you should do. Fartlek sessions become more overtly strength-based and more designed around current (and future goal) fitness. Here are a couple of ZAP Fitness standards:
#1 – Descending Tempo Fartlek (a.k.a. the "savage fartlek" from 8:19 steeplechase runner Jim Cooper):
- Begin this session with a 6:00 piece at roughly your anaerobic threshold, or close to half-marathon pace
- The recovery is half of the time of the piece (in this case 3:00)
- Run a 5:00 piece slightly quicker than the 6:00 (with the rest now being 2:30)
- Run a 4:00 piece a touch quicker (2:00 rest), 3:00 pick-ups (with 1:30 recovery), 2:00 pick-up (1:00 recovery)
- Finish with a 1:00 piece. The final two pieces of this fartlek should be working into the current 5K fitness range.
- For more advanced, higher-mileage athletes, begin with a 7:00 piece and go all the way down to 1:00.
#2 – Downcycle Fartlek: Also known as progression pieces, these are pick-ups that begin a bit slower and finish faster. My favorite is one we execute throughout the year at ZAP:
- After warming up, run a 2:30 pick-up beginning with the first 30 seconds only 5 to 10 seconds faster than your normal training pace. Each subsequent 30-second block should be a touch quicker than the previous with the final 30 seconds (from 2:00 to 2:30) being at or slightly faster than 10K fitness or race pace.
- Recover with 90 seconds jogging easily
- Run another 2:30 pick-up the same way.
I recommend running two sets, or a total of four pick-ups, which will take 16:00, including recovery.