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Based on analysis of photometric observations of nearby M type stars obtainedwith ASAS, 31 periodic variables were detected. The determined periods areassumed to be related to rotation periods of the investigated stars. Among them10 new variables with periods longer than 10 days were found, which brings thetotal number of slowly rotating M stars with known rotation periods to 12objects.  X-ray activity and rotation evolution of M stars follows the trends observedin G-K type stars. Rapidly rotating stars are very active and activitydecreases with increasing rotation period but the period-activity relation ismass-dependent which suggests that the rotation period alone is not a propermeasure of activity. The investigated stars were grouped according to theirmass and the empirical turnover time was determined for each group. Itincreases with decreasing mass more steeply than for K type stars for which aflat dependence had been found. The resulting Rossby number-activity relationshows an exponential decrease of activity with increasing Rossby number.  The analysis of space motions of 27 single stars showed that all rapidlyrotating and a few slowly rotating stars belong to young disk (YD) whereas allold disk (OD) stars are slowly rotating. The median rotation period of YD starsis about 2 days and that of OD stars is equal to 47 days, i.e. nearly 25 timeslonger. The average X-ray flux of OD stars is about 1.7 dex lower than YD starsin a good agreement with the derived Rossby number-activity formulasupplemented with rotation-age relation and in a fair agreement with recentobservations but in a disagreement with the Skumanich formula supplemented withthe activity-rotation relation.

Age-Rotation-Activity Relations for M Dwarf Stars Based on ASAS Photometric Data