The aim of our project is to quantify the effects of training modality on power development during a stair climb. Specifically, we want to determine whether average power during stair climbing is different in people who primarily train for endurance when compared to those who train primarily for strength. Findings from previous studies on the topic appear to be inconclusive due to power being both a function of speed and strength. A previous meta-analysis found that in youth athletes power training (low resistance, plyometrics) led to an improvement in power measures (Behm et al., 2017). Some studies involving elderly adults also echo these results as weighted step exercises and other forms of power training have been found to improve stair climb performance (Misko et al., 2003; Mair et al., 2019). These studies measured lower limb power output, leg extensor power, and anaerobic power in order to quantify stair climbing performance suggesting that power is a valid way to measure stair climbing performance. However, when looking at football players to see whether speed or strength training can lead to an increase in power development, the results were inconclusive (Wenzel & Perfetto, 1992). Thus, more insight into the individual effects of endurance and strength training on power development during a stair climbing task remain warranted. To this end, we are planning on recruiting young adults who will be categorized to either an endurance (EG) or strength (SG) group based on their training history. Participants from both groups will be instructed to perform a rapid stair climbing task under two different conditions: one with a shorter stair climb length and the other with a longer stair climb length. We are primarily interested in measuring the average power of a person running up a set of stairs, normalized by mass. This will act as our dependent variable. The average power will be calculated from data collected using smartphone sensors through the utilization of a MatLab-based application. We expect that strength focused participants will have a greater average power for the shorter stair climb length, while endurance focused participants will have a greater average power for the longer stair climb length. The PwrLab application that will be used throughout this study has the ability to be utilized in further studies. The smartphone sensors used by the PwrLab app also capture metrics that can lead to instantaneous power. A continuation of this project could look at how power development changes across different stair climbing distances which could lead to ideal distances for specific training. In a more widespread use, our PwrLab App can be used to test the efficacy of an intervention implemented to improve stair climbing mobility. An additional interesting hypothesis that could be tested is if an increase in average power generation while running up a flight of stairs correlates with increased speed during sprinting tasks and if so, can exercises used to increase power generation while climbing stairs be implemented as sprint training, since stair climbing is often cited as a good mode of training for sprinters? The results of the project are directly applicable to younger adults and athletes who are interested in improving their performance in power-based tasks. In addition, the results can also be applied towards elderly adults who wish to gain more independence in their daily tasks. Determining the individual effects of endurance and strength training on average power during stair climbing could help inform the development of training and rehabilitation programs that can maximize performance in tasks that have similar physical demands. **References:** Behm, D. G., Young, J. D., Whitten, J. H., Reid, J. C., Quigley, P. J., Low, J., . . . Granacher, U. (2017). Effectiveness of Traditional Strength vs. Power Training on Muscle Strength, Power and Speed with Youth: A Systematic Review and Meta-Analysis. Frontiers in Physiology, 8. doi:10.3389/fphys.2017.00423 Mair, J. L., Vito, G. D., & Boreham, C. A. (2019). Low Volume, Home-Based Weighted Step Exercise Training Can Improve Lower Limb Muscle Power and Functional Ability in Community-Dwelling Older Women. Journal of Clinical Medicine, 8(1), 41. doi:10.3390/jcm8010041 Miszko, T. A., Cress, M. E., Slade, J. M., Covey, C. J., Agrawal, S. K., & Doerr, C. E. (2003). Effect of Strength and Power Training on Physical Function in Community-Dwelling Older Adults. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences, 58(2). doi:10.1093/gerona/58.2.m171 Wenzel, RR. Perfetto EM. (1992). The Effect of Speed Versus Non-Speed Training in Power Development. Journal of Applied Sports Science Research, 6(2).