Although I cannot find specific activities, my educated guess would be that St. Thomas governed his leisure time along the lines of Josef Pieper's 1948 book Leisure: The Basis of Culture. Many reviews can be found on the goodreads website as well. A more extensive 2015 blog review is here. The epigraph of the book is from Psalm 46:11 : "Be at leisure -- and know that I am God"
Josef Pieper is a renowned Thomist scholar famous for writing lay accessible books on Aquinas's notion of virtues, whose books were recently republished by Ignatius Press.
I found a very good and practical teaching note on the book plus exploration of related concepts (reason & faith, idleness, work, and feast), all along Thomistic ideas, written by Dr. Michael Naughton of the University of St. Thomas .
I begin this course with an extensive exploration of what we mean by leisure, work, and their relationship. My thesis with the students, which I encourage them to challenge, is the following: if we don’t get leisure right we will not get work right. Behind these words of leisure and work is the relationship between the contemplative and active life, which describes what we receive and what we give. I have found that Josef Pieper‟s essay Leisure the Basis of Culture to be a profound analysis of these relationships and while it is the most difficult text the students read during the semester, it tends to ignite in them the paradigmatic change they need.
The teaching note has 5 sections:
An Introduction to the Meaning of Leisure: Since leisure is such a strange and old word to students, I give them a definition of what it means according to Pieper and how it has been used within the Western tradition.
Seeing Things Whole: Ratio (Reason) and Intellectus (Faith). The modern academic problem is that faith has become alienated from reason/ratio. To see all knowledge as only ratio marginalizes theological discourse from the university and eventually reduces reason to empirical reasoning which eventually marginalizes philosophy, literature, and the humanities in general.
Acedia: When we see the world only dependent upon reason or ratio, and increasing instrumental reasoning, we begin to experience acedia, the sin against leisure.
Proletariat: The predominant anthropological understanding of the modern person is increasingly the worker who is bounded by the process of work.
Feast: At the heart of leisure is festivity, which is the basis of leisure and of culture, and if we fail to see our feast as worship, and participate in false worship all the technological advancements and legal regulations will fail to save our culture.
To whet one's appetite to read the book itself, here is an Introduction to the 1998 edition (St. Augustine's Press) by Roger Scruton:
"Don't just do something: stand there!" The command of an American
President to a fussy official was one of those rare moments in
American politics when truth prevailed over industry. Josef Pieper's
serene reflections on the art of being serene ought to be read by every
practical person | and the more that person is involved in business,
politics, and public life, the more useful will Pieper be to him. For
here, in a succinct yet learned argument, are all the reasons for thinking
that the frenzied need to work, to plan, and to change things is
nothing but idleness under other names -- moral, intellectual, and
emotional idleness. In order to defend itself from self-knowledge, this
agitated idleness is busy smashing all the mirrors in the house.
Leisure has had a bad press. For the puritan it is the source of vice;
for the egalitarian a sign of privilege. The Marxist regards leisure as
the unjust surplus, enjoyed by the few at the expense of the many.
Nobody in a democracy is at ease with leisure, and almost every
person, however little use he may have for his time, will say that he
works hard for a living -- curious expression, when the real thing to work is dying.
The calumnies, however, do not apply: so argues Josef Pieper. We
mistake leisure for idleness, and work for creativity. Of course, work
may be creative. But only when informed by leisure. Work is the
means of life; leisure the end. Without the end, work is meaningless
-- a means to a means to a means ... and so on forever, like Wall
Street or Capitol Hill. Leisure is not the cessation of work, but work
of another kind, work restored to its human meaning, as a celebration
and a festival. [bold added by me]
This is what religion teaches us, and the teaching is as important
for the unbeliever as for the person of faith. We win through to
leisure. "At the end of all our striving" we rejoice in our being and
offer thanks. It is then, eating a meal among those we love, dancing
together at a wedding, sitting side by side with people silenced by
music, that we recognize our peculiar sovereign position in the world.
Our failure to understand leisure, Pieper makes clear, is one with
our failure to understand the difference between man and the other
animals. Think only of meal-times -- and on this subject Pieper
writes with uncommon perceptiveness. The meal, as Pieper puts it,
has a "spiritual or even a religious character". That is to say, it is an
offering, a sacrifice, and also - in the highest instance -- a sacrament,
something offered to us from on high, by the very Being to whom we
offer it. Animals eat, but there is nothing in their lives to correspond
to this experience of the "meal", as a celebration and endorsement of
our life here on earth. When we sit down to eat, we are consciously
removing ourselves from the world of work and means and industry, and facing outwards, to the kingdom of ends. Feast, festival, and
faith lift us from idleness, and endow our lives with sense.
Pieper's book is also a feast. With astonishing brevity, he extracts
from the idea of leisure not only a theory of culture and its significance,
not only a natural theology for our disenchanted times, but
also a philosophy of philosophy - an account of what philosophy can
do for us, and what it ought to do for us, in a world where science
and technology have tried to usurp the divine command. And he
reiterates that command as it came in a "still small voice" to Elijah,
and again to Pascal and Kierkegaard: in his own gentle way, Pieper
tells us to "Be still".