**5. Conclusions**

To conclude, we found that adult human grip strength was influenced by a variety of factors, including age, sex, hand shape, and hand dominance asymmetry (i.e., laterality), consistent with previous studies. We also demonstrated for the first time that (1) grip strength varies throughout the lifespan, with more pronounced differences at specific life stages and (2) that the practice of different manual activities through occupation and sport

also influence grip strength, particularly in males. These results emphasise the importance of physical manual activities for the attenuation of age-related grip strength loss in a clinical context. These findings may also inform ergonomic research on modern anthropotechnical systems that rely on grip strength data [128,129]. Our results highlight the importance of studying the grip strength of both hands, rather than just the dominant hand, in relation to the above factors, to better understand the link between form and function of the hand, in both modern populations and in our evolutionary past.

**Supplementary Materials:** The following are available online at https://www.mdpi.com/2073-899 4/13/7/1142/s1, Figure S1: Distribution of participants used in the analyses according to ages groups and with right-handed (R) and left-handed (L) participants, Figure S2: Predictor effect plots for the fitting linear models of the interaction between age and hand shape for grip strength in female, for the dominant hand (A) and the non-dominant hand (B), Table S1: Details of the difference in percentage between hand grip strength in dominant and non-dominant hands for each sex (M = males;F= females) and age groups, according to right and left-handers, practicing of sport and the different occupations.

**Author Contributions:** Conception and Design of the research, G.S.F., G.D., T.E., T.L.K., A.B., H.B., C.S.; Data Acquisition, G.S.F., G.D., T.E., T.L.K., A.B., H.B., C.S., K.T.; Analysis, A.B., K.T.; Writing— Original Draft Preparation, A.B.; Writing—Review and Editing, A.B., T.L.K., G.S.F., G.D., T.E., H.B., C.S.; Project Administration, G.S.F.; Funding Acquisition, G.S.F. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by The Waterloo Foundation, gran<sup>t</sup> number 917-3756.

**Institutional Review Board Statement:** The study was conducted according to the guidelines of the Declaration of Helsinki, and approved by the Department of Psychological Sciences Ethics Committee at Birkbeck (ref: 181996, 14/05/2019), University of London.

**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.

**Acknowledgments:** We thank the London Science Museum and the Live Science scheme for allowing us to conduct this study, and the visitors who agreed to be part of the citizen science collaboration project called Me, Human. We thank the volunteers and research assistants: M. Ali, M. Diletta, R. Filippi, L. Fish, E. Forrester, S. Forrester, A. Ghanemi, C. Grevel, J. Hall, E. Jackson, C. Marsh, B. Meyer, S. Pem, E. Periche, E. Ranzato, Y. Slaveva, B. Stewart, and B. Todd for their help in collecting participant data. The authors thank the reviewers for their helpful comments, and Antoine Balzeau for the invitation to submit our work in the special issues "Symmetry in Human Evolution, From Biology to Behaviours".

**Conflicts of Interest:** The authors declare no conflict of interest.
