Improving running economy by cutting easy runs and only doing hard ones
Hey, I should start with a bit of context.
I started running in July 2023. It was just a lot of walking with some running in between. Nothing consistent.
In 2024 I've build to consistent 2-3 hours of running per week despite stressful job and a lot of travel and long hours. That's when noob gains started. First sub 30 5k and so on.
2025 was a lot more consistent, I was doing like 2-4h per week of running while working the same job. That's when I've did my 5k pr (25 flat).
I was always using some kind of plan with easy running, threshold reps, etc.
Now here comes cycling. I've done some longer rides like 70-120k but it was like once per 5 months and I've ran in between. Then I started cycling seriously in October 2025. I've bought kickr and started to build volume with Ironman plan with swim cut off (I don't swim, I just wanted to combine running and cycling). I could do that because I've quit my job and went to university so I only had to study and could recover better. I started with 5h combined and ended with average of 9h at the end of 2025.
Plan was still something like halfway in the beginning of 2026 so I've built more volume, with peaks around 13h combined. I was recovering well and still am. The issue was that my times at running stalled and I was getting stronger on a bike. I attributed it to doing high volume (for me).
So when the plan ended, I've done trail marathon to celebrate, then started olympic plan to use "base" to sharpen myself and bring my times down.
Despite this shift, my running times and economy just stalled.
Mind you, I've added 35w to my FTP since October 25 (I'm sitting now at 3,6w/kg so it's not really comparable to 25min 5k as it is much better than running time) and times in running are the same. Now I have one hard week before FTP test, but I'm certain that I will add like 10w at that test, seeing how lately my power to hr ratio is trending.
Now I have a pause between semesters and no obligations (3 months) so I would like to use it the best I can. I've thought about concentrating only on running, so building to 5-6h per week and ditching a bike. But with that I wouldn't utilise the time properly.
I also think about cutting easy volume in running and only doing sessions. And to relegate time cut from running to cycling. I still can't hold z2 during easy runs so (determined by LTHR field test regularly).
I would like to do even more volume but even I ask myself if it is viable option when my times are so pathetic and it is relatively high volume even for much more accomplished athletes.
TLDR: I've stalled hard at running at slow times and I'm much stronger on a bike. What's the best course of action if I want to improve running, yet don't want to cut cycling?
PS: I know that I should stop competing myself to others but even comparing myself to myself it's pretty bad.