Their diet was organic:
"A couple of kettles served them well for many years, but when rust finally overcame them, the only replacements they could fashion came from birch bark. Since these could not be placed in a fire, it became far harder to cook. By the time the Lykovs were discovered, their staple diet was potato patties mixed with ground rye and hemp seeds"
And they got plenty of outdoor exercise:
"Lacking guns and even bows, they could hunt only by digging traps or pursuing prey across the mountains until the animals collapsed from exhaustion. Dmitry built up astonishing endurance, and could hunt barefoot in winter, sometimes returning to the hut after several days, having slept in the open in 40 degrees of frost, a young elk across his shoulders."
And they were able to live close to nature:
"Wild animals destroyed their crop of carrots, and Agafia recalled the late 1950s as 'the hungry years.' 'We ate the rowanberry leaf' she said,
roots, grass, mushrooms, potato tops, and bark, We were hungry all the time. Every year we held a council to decide whether to eat everything up or leave some for seed.
Famine was an ever-present danger in these circumstances, and in 1961 it snowed in June. The hard frost killed everything growing in their garden, and by spring the family had been reduced to eating shoes and bark. Akulina chose to see her children fed, and that year she died of starvation. The rest of the family were saved by what they regarded as a miracle: a single grain of rye sprouted in their pea patch. The Lykovs put up a fence around the shoot and guarded it zealously night and day to keep off mice and squirrels."
They didn't waste any time watching TV, because they got to use their time productively hand crafting clothes:
"They fashioned birch-bark galoshes in place of shoes. Clothes were patched and repatched until they fell apart, then replaced with hemp cloth grown from seed."