It grows up to 12 feet tall in USDA zones 5 through 9. Another shrub, called the wayfaringtree viburnum (Viburnum lantana Mohican), grows 7 or 8 feet tall, blooms for three weeks in May and produces orange-red berries in July that ripen to black near summer's end. It grows in USDA zones 4 through 8.
fast-twitch (FT) fiber. a muscle fiber that can develop high tension rapidly. It is usually innervated by a single alpha neuron and has low fatigue resistance, low capillary density, low levels of aerobic enzymes, and low oxygen availability. FT fibers are used in such activities as sprinting, jumping, and weight-lifting.
These fibers rely heavy on the glycolytic energy system (using the method of anaerobic glycolosis to produce ATP). Type IIa fibers are in the middle of the muscle fiber spectrum, as they are less fatigue resistance, produce more muscular force, and contract at a faster speed than slow twitch fibers.Type IIb: Fast Twitch Fibers.or recreational athletes though, commitment to practice and training will play a far more significant role in performance level than muscle fiber type alone will. So, the three types of muscle fibers are slow twitch (Type I) and fast twitch (Types IIa and IIb).