Fig. 1

Trajectories of grip strength from age 53 to 69 in included participants (n = 446). A Individual maximum grip strength trajectories in all included Insight 46 participants, stratified by sex, and coloured by their assigned group from the GBTM based on a total of 3,078 NSHD participants (n = 7019 individual observations). Mean grip strength ± standard error (SE) error bars plus lower and upper quartiles (shown as diamonds) are shown for the included Insight 46 participants for each of the three study waves (age 53, 60–64, and 69). B Grip strength z-score trajectories for all included Insight 46 participants, coloured by their assigned trajectory group. Bold lines correspond to the estimated trajectory for each of the groups derived from the GBTM, with error bars showing 95 % CIs at the mean age of each study wave, and the bold squares are the mean grip strength z-score for each group at each study wave; note that the mean z-scores, estimated mean trajectories, and error-bars are based on all NSHD participants included in the model (n = 3078)