Why do you ask? You are a science denier. A flat-earther.
As science makes improvements in every area and including drugs so do drugs enable improvements in sport. That's what science does.
You only believe in science when it comes to drugs. You don't believe in science when it comes to shoes, bicarb, track surfaces, wavelights, improved training... You are a science denier.
13 out of 14 athletes improve their 1500m PB by around 2 seconds on average. Athletes from 6 different countries (7 if you count Habz as Moroccan) at ages ranging from 18 to almost 32.
How simple someone must be structured to think a single word - doping - can explain this properly?
Habz is a total fraud as we saw again today. Idk what happened in Paris that day, but the times should be thrown out. Habz and Koech are not 3:27 runners, Mills is not a 3:28 runner.