@article{gi chul ha2021and,
  title={Changes and differences in functional fitness among older adults over a four year period},
  author={seol jung kang,kwang jun ko,jae ryang yoon,cheol gyu yoo,seungtea park,gi chul ha},
  journal={Journal of Men's Health},
  volume={17},
  number={2},
  pages={70--76},
  doi = {10.31083/jomh.2021.002},
  year={2021}
}