Not a medical advice post!
Just wanting to share my experience with over training syndrome because I don’t think it fits the usual picture..
I am just a pretty normal runner not elite or anything but I managed to get a BQ time in 2025 (3:24)
Just after that, I decided to try to get my hormonal imbalance treated with hormonal BC pills. These immediately made me feel extremely sluggish, gained 3kg, felt depressed.
Easy runs felt hard and I would even get some chest pain. I stopped the pills after just 3 weeks, but during that time performance had dropped like a rock.
Monthly mileage during this time: 168 miles in the month before it started —> 81–>56
My training status in Garmin went to Unproductive, Overreaching and Detraining for about 8 weeks. I got tested at the doctor for Iron, COVID, thyroid and EBV. And the doctor did show potential recent EBV infection. They said they couldn’t tell if it was a reactivation or a previous / recovering infection.
I also got CRP and ECG to check heart health and it was clear.
I finally decided to take a bit of rest. I did exclusively slower bike riding for a little while and I think I probably took 1-2 weeks off. Because I thought it was EBV and that it was recovering, I thought I would get back to normal soon.
A 1 month from getting the EBV result, I did a Half marathon race and had a PB (1:37) but it was tough (avg HR 182).
Then a 1 month after that ran another marathon 3:33.
For the first time I had a bad stomach reaction to gels, serious muscle fatigue, and felt nauseous and super fatigued after the race. Had to lie down and rest for hours after with no appetite.
From November - March I committed to a new training plan where I increased mileage back up and only ran slow and sub threshold. I was seeing slow and steady progress until I increased mileage to 180 miles to prepare for my next marathon. I noticed when I picked up my mileage my performance seemed to reverse rather than improve and this made me consider other issues. I thought maybe I had post viral fatigue or POTS. I also was worried about having had myocarditis.
I got a chest MRI done, and it was clear. I had a lot of other tests they showed my Heart was “athletes” heart and I had good BP and good VO2 max (39.7) for my age and gender. However I knew my VO2 max could be better.
So I ran my next marathon in April 2026 - and this one a bit warmer than I’d want and my result was 3:48, average HR 187. Not as much fatigue after as before but I felt like crap during. Heavy legs and stress.
After this, and seeing how I was reacting harder training sessions (high hr, chest pain, fatigue), I decided to do a recovery block starting in June this year and ran 20-24 slow miles a week (under 140 HR, and that meant 11-12 min miles) and added swimming and weight training.
Still no progress has been made in my running times or paces, I am starting to get more fatigued every time I run. I also got a cold and a norovirus and I usually don’t get sick.
Then I learned about OTS. I’ve been feeling burnt out this whole year, I’ve been getting palpitations, I have also been feeling tired every morning. The recovery block and running less were the only times I started to feel slightly better but not 100%. It makes so much sense.
So I’m going to take a complete break from running for the first time in 2 years… I’ll reassess after 4 weeks but I might even take 12 weeks. Whatever it takes - I hope this resolves it for me. I used to be strong - never really got sick, never had an injury that lasted longer than 2 weeks, always recovered really quick from hard efforts. This made me realise I’ve altered my bodies response to stress now and made it weaker and I just need to reset.