My 2 cents...
- I have run a lot in my life and it is important to mix it up with other stuff
- ride a bike or swim to help with longevity of your joints/ligaments as they are lower impact alternatives for cardio. running puts a lot of wear and tear on the body. eventually this catches up with us all
- life weights and or do body weight exercises, this can be done at home, even a small amount of strength training will help your overall results a lot. if all you do is run the results won't be as good as a balanced approach to cardio and weights...by mixing in strength training it will force your body to build muscle which it wants to break down if all you do is cardio so it can become more efficient
- do sprints, if you look at the bodies of the sprinters and the distance runners what do you notice, the sprinters are jacked and the distance runners just look skinny, sprinting produces a greater GH release and will help with fat loss with less catabolism of muscle, you can do both but make sure sprinting makes up a decent portion of your running, run on grass with cleats when possible to reduce wear and tear
- I am sure you have your diet pretty much sorted given your awesome progress (congrats by the way, great achievement, not many people can do what you did so feel good about it) but there are people on this board and others that help with things like contest prep that can probably take you to the next level (without drugs) by simply tweaking your diet. for me Keto works great to strip the pounds off but everyone is different so you need to find out what works for you and dial it in.
- when the progress stalls and you are ready for drugs the ones I have found help with cardio are: Anavar, Cardarine, and Equipoise...the first two are very safe for women, the var helps burn abdominal fat and helps endurance a bit (for women 5-10mg/d is a good dose) the trick is finding legit var which is often faked with low dose TBOL or even DBOL, the Cardarine as previously suggested helps to metabolize fat and has the side effect of improving HDL/LDL but also some possible cancer risk which is low but not to be totally blown off, the Equipoise is a drug that they give to race horses which increases EPO which increases red blood cell production which means more oxygen transfer to your cells and will also put on some lean muscle but nothin dramatic at low doses (basically it'll help with recovery)...I can't remember the dose that is recommended for women but it's pretty low...the negative side effects of EQ are increased blood pressure, increased appetite, and possible anxiety if you are prone to it. It can cause virulization symptoms (making you more masculine) so you have to be careful with the dose and because it is a long acting injectable you can't pull the plug on it and clear it quickly, it takes weeks to drop so I would approach this with caution but I have known some women who like it a lot.
- sarms are probably a safer alternative to steroids if you just want to improve your stamina and recovery. Ostarine works well for women even at doses recommend for men without side effects and LDG-4033 seems to work well but will put on more muscle/weight so I would use a much lower dose than what is recommended for men. I am sure there are others but these are the ones I have lady friends that have used with success.
As the other posters have said, keep doing what you are doing cause it is working (don't fuck with a winning formula!) but when you hit a plateau and are ready to change things up the above is what I would recommend. drugs being the last step.
Good luck with your goals. keep up the good work.