नात्यश्नतस्तु योगोऽस्ति न चैकान्तमनश्नतः।न चातिस्वप्नशीलस्य जाग्रतो नैव चार्जुन॥
nātyaśnatastu yogo ’sti na caikāntam anaśnataḥna cāti-svapna-śīlasya jāgrato naiva cārjuna
Word by word
The verse says
Practice is not for the one who eats too much, nor for the one who does not eat at all — nor for one given to too much sleep, nor for one who stays awake, Arjuna.
In plain words
Four refusals, and two of them are aimed at the devout.
Eating too much and sleeping too much are ordinary failings.
Not eating and not sleeping are austerities, and they are refused in exactly the same breath.
Where you've felt this · in health
You try very early mornings for a fortnight and very late nights for another. Both weeks produce almost nothing. The boring hours in the middle turn out to be where the work actually lives.
Going deeper
The even-handedness of this verse is what makes it remarkable, and it is aimed at a particular kind of reader.
In a tradition with a long and admired history of fasting and sleeplessness, Krishna puts those beside overeating and oversleeping and rejects all four. The ascetic gets no more credit here than the glutton.
That is not a compromise position. It is a claim about what practice requires, which is a body and a mind that are working. Both ends of the scale disable the equipment.
And there is something quietly kind in it. Extremity is easier to admire and easier to perform than moderation, and it is often a way of not doing the harder ordinary thing.
The next verse makes the point positively, and between them they are the most practical pair of sentences in the book. Whatever else this chapter asks, it does not ask you to damage yourself.