Strides during easy run

Strides are a usefull routine but when and how much you should do them depends on many factors like :

What event are you preparing? Are you in base phase or specific phase for somes races? What is the balance of your training regarding speed work and aerobic stuff? What is the purpose of those strides in your training? Do you like doing strides? etc

If you do several workouts a week and are tired from it, you should keep the easy day as easy as possible imo. To goal is not to do work for improvmet on those days but to recover while logging some miles. Strides can be used for a purpose of recovery if they are ran very relaxed (like 5k pace) and not a lot of them (let's say 2 to 6 ). They help activate blood circulation and stretch sore muscles.

Another purpose of strides is to do speedwork and maintain speed quality along with running form while the training is focus on something else (usually in base phase or Threshold/VO2max phase for a middle distance runner). In this case it's like a mini workout often ran around mile pace or slightly faster. This is very usefull for middle distance runners off track season, usefull for 3-5k runners, less usefull for 10k and above but not useless either.

It can also be done as a V02max workout by doing a lot of them on the longer side (20-30sec) at mile/3k pace with short active rest. Like Rudisha diagonals workout.

If you don't like them at all, there are other ways to get what strides give but doing some every week is usually the easiest way.

I have found another benefit of strides on easy days. Have you ever found that an easy run at a low heart rate is not proving to be all that easy? IN other words, you start to get discouraged because you feel like you are putting way too much effort into what is supposed to be a simple recovery run.

Try doing 4 or 5 100 meter strides. Then the run goes much better. Not sure why. Maybe you are improving your form or recruiting more muscles into the easy run.

If you're trying to build muscular endurance, do your strides at the end of a long easy run, when they are fatigued. If you're trying to build power, do them when your legs are fresh.

So you mean i should do them before the easy run in a cold state?

I've noticed this before. Sometimes on an easy run I get stuck in a stiff-feeling, slow-funk pace where I feel terrible and even the slowest pace feels like an effort. Then I do a few strides, starting only slightly faster, then gradually progressing in speed with each one. After enough of them that my legs feel loosened up, I'm able to settle into an easy pace that feels easier, yet is faster than the slower pace I was stuck in before.

It's sort of like you have to shake the rust off, before the system will let you find more efficient gears.