Your friend heard wrong, Serfs in medieval england did though have more "vacation time" and a shorter work week, I'm just going to quote The Overworked American: The Unexpected Decline of Leisure, by Juliet B. Schor because I'm lazy and it already explains it well:

Consider a typical working day in the medieval period. It stretched from dawn to dusk (sixteen hours in summer and eight in winter), but, as the Bishop Pilkington has noted, work was intermittent - called to a halt for breakfast, lunch, the customary afternoon nap, and dinner. Depending on time and place, there were also midmorning and midafternoon refreshment breaks. These rest periods were the traditional rights of laborers, which they enjoyed even during peak harvest times. During slack periods, which accounted for a large part of the year, adherence to regular working hours was not usual. According to Oxford Professor James E. Thorold Rogers[1], the medieval workday was not more than eight hours. The worker participating in the eight-hour movements of the late nineteenth century was "simply striving to recover what his ancestor worked by four or five centuries ago."

An important piece of evidence on the working day is that it was very unusual for servile laborers to be required to work a whole day for a lord. One day's work was considered half a day, and if a serf worked an entire day, this was counted as two "days-works."[2] Detailed accounts of artisans' workdays are available. Knoop and jones' figures for the fourteenth century work out to a yearly average of 9 hours (exclusive of meals and breaktimes)[3]. Brown, Colwin and Taylor's figures for masons suggest an average workday of 8.6 hours[4].

The contrast between capitalist and precapitalist work patterns is most striking in respect to the working year. The medieval calendar was filled with holidays. Official -- that is, church -- holidays included not only long "vacations" at Christmas, Easter, and midsummer but also numerous saints' andrest days. These were spent both in sober churchgoing and in feasting, drinking and merrymaking. In addition to official celebrations, there were often weeks' worth of ales -- to mark important life events (bride ales or wake ales) as well as less momentous occasions (scot ale, lamb ale, and hock ale). All told, holiday leisure time in medieval England took up probably about one-third of the year. And the English were apparently working harder than their neighbors. The ancien règime in France is reported to have guaranteed fifty-two Sundays, ninety rest days, and thirty-eight holidays. In Spain, travelers noted that holidays totaled five months per year.[5]

The peasant's free time extended beyond officially sanctioned holidays. There is considerable evidence of what economists call the backward-bending supply curve of labor -- the idea that when wages rise, workers supply less labor. During one period of unusually high wages (the late fourteenth century), many laborers refused to work "by the year or the half year or by any of the usual terms but only by the day." And they worked only as many days as were necessary to earn their customary income -- which in this case amounted to about 120 days a year, for a probable total of only 1,440 hours annually (this estimate assumes a 12-hour day because the days worked were probably during spring, summer and fall). A thirteenth-century estime finds that whole peasant families did not put in more than 150 days per year on their land. Manorial records from fourteenth-century England indicate an extremely short working year -- 175 days -- for servile laborers. Later evidence for farmer-miners, a group with control over their worktime, indicates they worked only 180 days a year.

*Sources

[1] James E. Thorold Rogers, Six Centuries of Work and Wages (London: Allen and Unwin, 1949), 542-43.

[2] H.S. Bennett, Life on the English Manor (Cambridge: Cambridge University Press, 1960), 104-6.

[3] Douglas Knoop and G.P. Jones, The Medieval Mason (New York: Barnes and Noble, 1967), 105.

[4] R. Allen Brown, H.M. Colvin, and A.J. Taylor, The History of the King's Works, vol. I, the Middle Ages (London: Her Majesty's Stationary Office, 1963).

[5] Edith Rodgers, Discussion of Holidays in the Later Middle Ages (New York: Columbia University Press, 1940), 10-11. See also C.R. Cheney, "Rules for the observance of feast-days in medieval England", Bulletin of the Institute of Historical Research 34, 90, 117-29 (1961).*