Running workout disappeared

I completed a custom outdoor running workout. I ended the workout as usual but it has seemingly disappeared and I cannot access it anywhere. The data has recorded as the steps have logged, my heart rate has logged, my exercise rings have closed etc. but the workout itself is nowhere. I would like to access the workout as it was part of a training plan I am completing. Is there anyway that I can find a workout that appears to have been lost or mistakenly deleted?