Thaum peb muaj hnub nyoog, peb cov tawv nqaij hloov ntau yam, nrog rau kev loj hlob ntawm cov kab zoo, wrinkles, thiab poob ntawm elasticity. Txhawm rau tiv thaiv cov cim ntawm kev laus, ntau tus neeg tig mus rau lub ntsej muag tiv thaiv kev laus. Nrog rau ntau txoj kev xaiv muaj nyob rau hauv kev ua lag luam, xaiv txoj cai los tiv thaiv kev laus lub ntsej muag yuav ua tau yooj yim. Hauv phau ntawv qhia no, peb yuav tshawb xyuas cov ntsiab lus tseem ceeb los txiav txim siab thaum xaiv qhov zoo tshaj plaws los tiv thaiv kev laus lub ntsej muag rau koj cov tawv nqaij.