@article {7586, title = {Leisure-time physical activity and leukocyte telomere length among older women.}, journal = {Exp Gerontol}, volume = {95}, year = {2017}, month = {2017 Sep}, pages = {141-147}, abstract = {

BACKGROUND: Shortened leukocyte telomere length (LTL), a purported marker of cellular aging, is associated with morbidity and mortality. However, the association of physical activity, a modifiable lifestyle behavior, with LTL has not been adequately studied among older adults.

METHODS: In this cross-sectional study, we examined associations of various intensity levels of leisure-time physical activity with LTL among 1476 older white and African American women from the Women{\textquoteright}s Health Initiative Objective Physical Activity and Cardiovascular Health study. Self-reported physical activity was assessed by questionnaire, and LTL was measured by Southern blot. The association between physical activity and LTL was evaluated using multiple linear regression models adjusted for demographic characteristics, lifestyle behaviors, and health-related variables.

RESULTS: Women were on average aged 79.2 (standard deviation 6.7) years old. In the final model adjusted for age, race/ethnicity, education, marital status, smoking, alcohol, body mass index, a history of chronic diseases, and hormone therapy use, LTL was on average 110 (95\% confidence interval, 20-190) base pairs longer among women in the highest (>=17.00MET-hours/week) compared with the lowest (<1.25MET-hours/week) level of total leisure-time physical activity (P for trend=0.02). Higher levels of moderate-to-vigorous physical activity (P for trend=0.04) and faster walking speed (P for trend=0.03) were also associated with longer LTL in the fully-adjusted models.

CONCLUSION: Older women participating in greater amounts of total leisure-time physical activity and moderate-to-vigorous physical activity had longer LTL.

}, issn = {1873-6815}, doi = {10.1016/j.exger.2017.05.019}, author = {Shadyab, Aladdin H and Lamonte, Michael J and Kooperberg, Charles and Reiner, Alexander P and Carty, Cara L and Manini, Todd M and Hou, Lifang and Di, Chongzhi and Macera, Caroline A and Gallo, Linda C and Shaffer, Richard A and Jain, Sonia and LaCroix, Andrea Z} } @article {8989, title = {What Cut-Point in Gait Speed Best Discriminates Community-Dwelling Older Adults With Mobility Complaints From Those Without? A Pooled Analysis From the Sarcopenia Definitions and Outcomes Consortium.}, journal = {J Gerontol A Biol Sci Med Sci}, volume = {76}, year = {2021}, month = {2021 09 13}, pages = {e321-e327}, abstract = {

BACKGROUND: Cut-points to define slow walking speed have largely been derived from expert opinion.

METHODS: Study participants (13 589 men and 5043 women aged >=65years) had walking speed (m/s) measured over 4-6 m (mean {\textpm} SD: 1.20 {\textpm} 0.27 m/s in men and 0.94 {\textpm} 0.24 m/s in women.) Mobility limitation was defined as any self-reported difficulty with walking approximately 1/4 mile (prevalence: 12.6\% men, 26.4\% women). Sex-stratified classification and regression tree (CART) models with 10-fold cross-validation identified walking speed cut-points that optimally discriminated those who reported mobility limitation from those who did not.

RESULTS: Among 5043 women, CART analysis identified 2 cut-points, classifying 4144 (82.2\%) with walking speed >=0.75 m/s, which we labeled as "fast"; 478 (9.5\%) as "intermediate" (walking speed >=0.62 m/s but <0.75 m/s); and 421 (8.3\%) as "slow" (walking speed <0.62 m/s). Among 13 589 men, CART analysis identified 3 cut-points, classifying 10 001 (73.6\%) with walking speed >=1.00 m/s ("very fast"); 2901 (21.3\%) as "fast" (walking speed >=0.74 m/s but <1.00 m/s); 497 (3.7\%) as "intermediate" (walking speed >=0.57 m/s but <0.74 m/s); and 190 (1.4\%) as "slow" (walking speed <0.57 m/s). Prevalence of self-reported mobility limitation was lowest in the "fast" or "very fast" (11\% for men and 19\% for women) and highest in the "slow" (60.5\% in men and 71.0\% in women). Rounding the 2 slower cut-points to 0.60 m/s and 0.75 m/s reclassified very few participants.

CONCLUSIONS: Cut-points in walking speed of approximately 0.60 m/s and 0.75 m/s discriminate those with self-reported mobility limitation from those without.

}, keywords = {Aged, Female, Gait, Humans, Independent Living, Male, Mobility Limitation, Sarcopenia, Walking, Walking Speed}, issn = {1758-535X}, doi = {10.1093/gerona/glab183}, author = {Cawthon, Peggy M and Patel, Sheena M and Kritchevsky, Stephen B and Newman, Anne B and Santanasto, Adam and Kiel, Douglas P and Travison, Thomas G and Lane, Nancy and Cummings, Steven R and Orwoll, Eric S and Duchowny, Kate A and Kwok, Timothy and Hirani, Vasant and Schousboe, John and Karlsson, Magnus K and Mellstr{\"o}m, Dan and Ohlsson, Claes and Ljunggren, Osten and Xue, Qian-Li and Shardell, Michelle and Jordan, Joanne M and Pencina, Karol M and Fielding, Roger A and Magaziner, Jay and Correa-de-Araujo, Rosaly and Bhasin, Shalender and Manini, Todd M} }