Single-Session Workouts for Marathoners -Why training once a day can work to your advantage
I found this very interesting. I have often fretted about the fact that I have not been able to successfully incorporate "doubles" into my training schedules. I had generally formed the view that it was one of the things, apart from a lack of natural ability, that was preventing further improvements in performances.
My training for the Perth marathon was almost solely singles and on reading this article, I think I can see why I had a successful marathon as a program based on singles seems to play to my strengths - ie endurance rather than speed, mental toughness and efficient fat burning at marathon pace.
So while I found this reassuring, I also found something very worthwhile in this article:
Marathon Performance Training Group’s elite coach Brad Hudson says the magic number to hit in a single run is 80 minutes. “A lot of the science shows that once you reach the 80-minute mark, there is a bigger benefit in endurance enzymes made.” Hudson notes that studies have shown that the differences of enzymatic production from 60 to 80 minutes are enormous.
Long singles also make you a stronger runner. The longer amount of time spent during one session increases the flow of blood to the muscles. Ligaments and tendons are strengthened; capillaries grow and more oxygen can be delivered to the working muscles. Additionally, completing training in singles allows the body more rest. “When you are doing singles, you are giving the body a full 24 hours of rest,” Hudson points out.
One of the things that has discouraged me from doing doubles has been the shortened recovery time between runs. If I was 20 years younger, I wouldn't be concerned about this at all, but I haven't seen one reputable source/coach that recommends doubles for masters runners, basically because as you get older, you need more time to recover.
Anyway, here is a link to the article: