later will be bitter"

So I had an idea.
I grabbed my MP3 player and trainers and decided to go for a run instead!
It's pretty cold outside in England at the moment. I mean, not as cold as it gets in January, but today it was about 9 degrees, with a 12mph wind - not on my side either!
My throat was burning from the cold air and even my teeth, gums and inside my ears were cold! Not surprisingly I didn’t see any other runners this evening.
I know my route well because it's towards, around and back from my local park and, up until about summer last year, I used to run the route regularly. It's about 3 miles long. Last spring I was training for a race at the time I was doing a lot of cardio, weekly including outdoor running.
The weird thing is my run today felt so easy and unforced. My body felt light and totally efficient, my steps and movements were rhythmic. I didn’t even get tired the whole time. And despite the cold air, it was so enjoyable. I felt so alive in the cold.

Last year, and any other time I've trained for a race, I never ever felt this strong.
Now I know I'm really fit!
I can really feel it! Fitter than I've ever been. Fitter, stronger, healthier! I can only imagine how great I'm going to feel in 3 weeks time when I have reached the peak. I can't wait!
The old Chinese proverb rings so true: "Taste bitter now and later will be sweet. Or experience only the sweet then later will be bitter".
We're coming to the end of the PCP now. All the training and diet wasn’t (isn’t) easy. It takes a lot of dedication and consistent motivation. The workouts are every single day without rest and the diet, although highly nutritious and always filling, is simple and basic and often boring. I mean 7 egg whites a day, at one point!
No cake, no wine, no Take-aways - It has been hard.
But, coming to the end of the PCP, it was totally worth it.
Now that I can really see the fruits of my labour, in so many ways, I can totally appreciate that old Chinese proverb.