Swimming acceleration and velocity are the net balance between Drag Force and Thrust. It is a standard procedure to do the decomposition of the Thrust-Time curve, assessing the swimmer’s thrust. However, there is not a convention or standard procedure on the variables to be selected. Researchers report on regular basis either the Peak Thrust, Mean Thrust or Thrust-Time Integral. It is yet unclear to which extend these variables can be used, reported and interpreted interchangeably. PURPOSE: To analyze the association between different thrust variables performing arm-pulls in competitive swimming. METHODS: 671 front-crawl arm-pull cycles of 14 competitive swimmers were analyzed. Thrust was collected by an in-house built system composed by differential pressure sensors and underwater camera (Aquanex, Swimming Technologies, USA). A customised software (LabVIEW®, v.2017) was used to acquire (f=50Hz) and streaming time-series and video signal. Data was transferred to interface by a 14-bit resolution acquisition card (NI-6001, National Instruments, Austin, USA). Then, it was imported into a signal processing software (AcqKnowledge v.3.9.1, Biopac Systems, USA). It was extracted the Peak Thrust, Mean Thrust and Thrust-Time Integral of each arm-pull. Coefficients of Determination were computed between the three thrust variables. RESULTS: All Coefficients of Determination were significant (P<0.001). Peak Thrust vs. Mean Thrust was R²=0.49, Peak Thrust vs. Force-time Integral R²=0.51, and Force-time Integral vs. Peak Thrust R²=0.61. Interception on Y-axis at the origin of the pairwise variables noted in the same SI unit (i.e. Newton) were very close to zero (-1.6948<c<4.5029) and standard error of estimate acceptable (6.54<S<12.14). CONCLUSIONS: There is a strong association between different thrust variables, even though the proportion of the variance is about 50-60%. Supported by: NIE AcRF Grant (RI 6/17 TB); Portuguese Foundation for Science and Technology (UID/DTP/04045/2019); European Fund for regional development (FEDER)-COMPETE 2020 (POCI-01-0145-FEDER-006969).