That is Joseph Brodsky, who for all his brilliance and erudition had English as a second language. That left him free to do as he pleased with it. That "the Russian life " does strike me a bit odd at first, but I see where he got it. It is better than the alternatives. By "the Russian life in those days", he meant something like "the kind of life led by a Russian of those days"—"life" in his conte
This is exactly where the problem lies which has made me lose a lot of sleep.
In English, when we use OF, almost on every occasion we need THE; the usual explanation I see is, when OF exists, it refers to a possessive relationship, which entails definiteness, so we need a definite article THE. But this reason, I have long found, is feeble.
You could add "the", but the problem with the definite article in this case is that it presupposes that there is indeed tension in your shoulders and back. The sentence as it stands, "Massage can relieve tension in your shoulders and back", means that massage can relieve any tension that might exist in one's shoulders and back.