Oxendale, ChelseaHighton, JamieTwist, CraigSmith, Grace2022-07-132022-07-132022-07-07Oxendale, C. L., Highton, J., Smith, G. & Twist, C. (2023). Can player tracking devices monitor changes in internal response during multidirectional running?, Research Quarterly for Exercise and Sport, 94(4), 975-981. https://doi.org/10.1080/02701367.2022.20920490270-136710.1080/02701367.2022.2092049http://hdl.handle.net/10034/627017This is an Accepted Manuscript of an article published by Taylor & Francis in Research Quarterly for Exercise and Sport on 07/07/2022, available online: 10.1080/02701367.2022.2092049Purpose: We examined the movement, physiological and muscle function responses to running with and without (i.e. linear) multiple directional changes to understand which measures of external demands better reflected changes in the internal response. Methods: Twelve team sport athletes completed a linear and multidirectional running trial during which movement characteristics, oxygen consumption (), blood lactate (B[La]) and heart rate (HR) were measured. Isometric peak torque of knee extensors and flexors was also assessed before and after each trial. Results: High speed running distance was higher during the linear trial (p < 0.001), whereas time at high metabolic power (p = 0.046), number of accelerations (p < 0.001), summated HR (p = 0.003) and B[La] (p = 0.002) were higher during the multidirectional trial. Integrated external to internal ratios of high-speed running: summated HR and high-speed running: total were different between multidirectional and linear trials (p ≤ 0.001). Conversely, high metabolic power: summated HR and high metabolic power: total were similar (p ≥ 0.246). Small decrements in knee flexor (p = 0.003) and extensor torque (p = 0.004) were observed after both trials. Conclusion: Time at high metabolic power better reflects the increased internal response during running with more directional changes than high speed runninghttps://creativecommons.org/licenses/by-nc-nd/4.0/AccelerationsExternal GPSInternal ratioMetabolic powerArticle2168-3824Research Quarterly for Exercise and Sport