Khairunnisa, S., Hidayah, N. and Pitriani, P. 2026. The Relationship Between Aerobic Capacity and Stroke Efficiency In 50 Meter Breaststroke Swimmers . Indonesian Journal of Physical Education and Sport Science. 6, 3 (Sep. 2026), 449-459. DOI:https://doi.org/10.52188/ijpess.v6i3.2262.