Yup, you read it correctly – fartlek is Swedish for Speedplay. It is a fun running exercise that serves as intro to speedwork. In my long run today, I added fartlek surges to increase my running intensity.
11 miles long w/7 x 90 sec surges (start at mile 5) w/5 min easy between each surge.
The trail this morning was not super crowded, so I did not have to worry much about crashing into someone during my fartlek surges. Plus not wearing a watch (running by feel), I estimated the time (90 seconds and 5 minutes) using my cadence of 180 ( 270 and 900 respectively).
All good. The surges was comfortable and controlled pace. At this base run phase of my marathon training, they did add intensity to my run and made second half of my long run gone by faster. My body was properly tired but not exhausted.
Have you tried the fartlek surges?