I’ll try, but it’s probably outwith the scope of a forum post!! Maybe best illustrated by examples…
I see the core principle of mindfulness as acceptance without judgement. I leave no stone unturned when prepraing for a race, and I pay particular attention to the weather forecast. I was scheduled to race a tight circuit and rain was forecast about 30 mins into the race. Right on cue the rain came down. The usual reaction would be to start complaining about the rain, begin to worry about how to take the corners, start second guessing have I got the tyre pressures right, worrying about whether other riders are going to crash around me and then get angry with folk that start making mistakes. All these are judgements, and can affect our abilty to be effective in our task. The mindful approach was to notice without judgement. It’s raining. Nothing else. Once you free yourself from the judgements about the rain, you can be more effective in remaining focussed on what’s going on. I remember the smell of the rain on the wet tarmac, and that’s the last I recall about the rain. I remained focused on staying in the bunch, and aware without critisism or judgement of those around me. Instead of thinking “he’s got that corner wrong, I hope he doesn’t hit me”, I think “he has taken a very wide line. I need to adjust mine.”
I apply the same principle to hard sessions. Instead of dreading VO2 max sessions, thinking this is going to hurt, I’ll think I need to hold X watts for X minutes. I notice the sensations in my legs and pay attention to my cadence/pedal stoke. I don’t consider it pain, as that’s a judgement, but notice the sensation.
Last nights Zwift race, I planned to split the field at a certain climb. Instead of going up there, screaming with pain, approached it calmy. Planned “I will ride at 600W for 30s up here. Power is a number.” I did what I set out, noticed my effort and the 4s gap on the field. The effort had worked but hadn’t planned to be off the front, so had to make a decision on the fly what to do. Noticed my HR, and the sensation in my legs and made a decision to wait sit up. That was the choice I made. Being angry/upset etc would not have changed it, but I could change the path I would take for the rest of the race.
For me, it really works.