The samples of polyamide 6.10 were subjected to strains by stretching-compression and by bending at temps. in the range from -140 degrees C to 140 degrees C. The tests were conducted for single cycle and multiple cycles, for previously loaded as well as unloaded samples. Dynamic anal method and differential scanning calorimetry were used to det. values of mech. lossi-ness factors and degrees of crystallinity, resp. Cyclic loads of polyamide samples resulted in a decrease in the value of its mech. lossiness factors and degree of crystallinity.