Performance, reliability and fatigue in prone bridge test and supine unilateral bridge test

The core muscles can be evaluated through functional tests, such as the prone bridge test (PBT) and supine unilateral bridge test (SUBT). However, there are differences in reliability and muscle fatigue related to these tests.The study evaluated 30 sedentary individuals and 30 individuals who practiced resistance exercises. Participants performed the PBT and SUBT in association with muscle recruitment, through surface electromyography of the upper and lower limbs and trunk muscles. The order of the tests was random and the participants performed one repetition of each test until fatigue. After a 30-min rest interval the participants repeated the tests. After one week, the participants returned and repeated the tests.The resistance group (RG) presented longer PBT holding time (RG 111.8 ± 9.4 and sedentary group (SG) 81 ± 7.7; p = 0.01), while the holding time in the SUBT was similar for both groups (RG = 100.7 ± 8.1 and SG = 79 ± 9.2; p = 0.09). Good to excellent reliability (ICC0.836; SEM 3.85) was established for the PBT and SUBT. Comparing the two groups there were no significant differences or interactions regarding muscle fatigue. The intragroup analysis on the PBT indicated greater gluteus maximus muscle fatigue, and for the SUBT the rectus abdominis presented greater fatigue, in both groups.The PBT and SUBT are reliable. Resistance exercise practitioners maintain the PBT for a longer time. The PBT led to greater gluteus maximus muscle fatigue, while the SUBT generated greater fatigue in the rectus abdominis and gluteus medius, in both groups.