M Easy reading, (200 pages, Penguin Classics, 2 coffees)
T Group read, (3 chapters, PhD-specific)
W Easy reading
T Speed read work (15 mins revision followed by 20x20 flash cards 10s on, 10s off)
F Easy reading
S Long Solo Read (3x Tomes, Library, 8hrs straight)
S Cross-reading, easy effort, history of Art
50+ miles, or 42+ miles the meaning of life is the answer. Sub 40 is very low.
Personally I need lots of volume to improve, so if I used my personal bias I would state a silly number not suitable for many.
Lower volume and a touch more intensity Id destroy myself in no time.
It is where a good coach can come in and work this stuff out quickly without years of trial and error for a particular individual and wasted effort (possibly avoid needless injuries)
This is one of the things Ive learnt coaching adults, not many have the time or patience and many just want to go out, run hard and feel tired and whilst it might not be the best way to a pb, if they enjoy it and it gets them out the door more often, why not. I have one guy at the moment, training from low base to 70.3 but he likes a weekly hard session, so i let him have one most weeks.