Today\u2019s guest is Bas Van Hooren, applied sport scientist and strength and conditioning specialist from the Netherlands.\u00a0 Bas has a wealth of knowledge 上 many facets of speed and sports performance, including muscle slack, muscle action, and biarticular muscle action, and how these concepts apply to training. Bas Van Hooren is an athlete, applied sport scientist and strength and conditioning specialist from Gronsveld, The Netherlands.\u00a0\u00a0 He is currently lecturing at Fontys University of Applied Sports Sciences.\u00a0 As an\u00a0athlete, Bas has won multiple medals at the national championships, including a gold medal at the national championship 3000m indoor in 2017. As an\u00a0applied sport scientist, Bas has written multiple peer-reviewed scientific publications about a variety of sport science topics, and has a special interest in the transfer effects of training 上 sports performance and injury prevention. It seems to happen regularly that we are reframing the context by which we are seeing and using traditional lifting with traditional up and down tempos.\u00a0 \u00a0The more we know about the exact physiological and neurological mechanisms that drive movement, the more we can understand which aspects of lifting, plyometrics, and special strength are helpful, and which might have a \u201creverse transfer\u201d. In my interview today with Bas, we go into detail 上 concepts of muscle slack, gearing, and phasic considerations, all with clear applications to how and what we are programming for our athlete populations. Today\u2019s episode is brought to you by SimpliFaster, supplier of high-end athletic development tools, such as the Freelap timing system, kBox, Sprint 1080, and more. View more podcast episodes at the podcast homepage. Key Points: \tBas\u2019 background in sport science, athletics, and performance \tHow the eccentric phase plays out in sport movement versus explosive isometric movements \tMuscle gearing and muscle pennation concepts and effect 上 coordination \tPractical thoughts 上 training the hamstrings \tUsing traditional up-and-down lifting in light of coordination \tMuscle slack and its effect 上 sport movement \tHamstring length and running\/sprinting \u201dLengthening of the whole muscle tendon unit does not necessarily reflect lengthening of the fascicles or muscle fibers\u2026. Look at what happens to the muscle fibers, and they may not always have an eccentric component while the muscle tendon unit is lengthening\u201d \u201cA lot of researchers believe that especially eccentric training has the largest effect 上 increasing fascicle length, but when you then take a more critical look at the studies, then you can say perhaps it\u2019s the movement velocity or the intensity that has the effect 上 fascicle length and not just contraction type\u201d \u201cA lot of people 上 ly consider, well if I do this exercise will performance will improve, but they don\u2019t think about possible negative effects to coordination, and 上 the structural level, pennation angle and fascicle length\u201d \u201cIf you increase strength of a muscle without improving coordination, performance will decrease\u201d \u201cWe defined muscle slack as the delay between muscle contraction, and the recoil of the series elastic elements in the muscle\u201d \u201cIt\u2019s quite possible that doing countermovements during training leads to an increase in muscle slack because an athlete\u2019s ability to produce co-contractions may be reduced as a result of the supporting effect of countermovement\u2026 essentially the athlete gets used to the countermovement, reducing muscle slack, and therefore does not create pretension to minimize muscle slack, so essentially, the central nervous system becomes lazy\u201d \u201cExternal load is not an appropriate strategy to reduce the effect of muscle slack in an acute way\u201d \u201cIf muscle fibers are very highly activated, they function at close to optimal length where they produce the most force\u201d Show Notes Single leg roman chair hold https:\/\/www.youtube.com\/watch?vu2EmpeN7t0E About Bas Van Hooren Bas Van Hooren is an athlete, applied sport scientist, and strength and conditioning specialist from Gronsveld, The Netherlands.\u00a0\u00a0 He is currently lecturing at Fontys University of Applied Sports Sciences. As an\u00a0athlete, Bas has won multiple medals at the national championships, including a gold medal at the national championship 3000m indoor in 2017. As an\u00a0applied sport scientist, Bas has written multiple peer-reviewed scientific publications about a variety of sport science topics, and has a special interest in the transfer effects of training 上 sports performance and injury prevention. Bas has trained individuals ranging from the elite to recreational level with a special interest in sports that involve running.\u00a0 He has a bachelor in applied sport sciences at Fontys University and a master's Human Movement Sciences at Maastricht University.