The scoop? This study found that Akhal-Tekes’ muscle mass is made up of about 50% slow-twitch muscles, which are the muscles types that are resistant to fatigue and allow for muscular endurance and regeneration. The other approximate half is formed by fast-twitch muscles, which are muscle types for explosive energy but more prone to fatigue and slower recovery. The concentrations of the two types in Akhal-Tekes are similar to those found in Arabians and Thoroughbreds, supporting the Akhal-Tekes’ famous capacity for both stamina and speed.
Excerpt from the study:
"The results of this study indicate that the MyHC I and IIa isoforms form about 50% of the skeletal muscle MyHC isoforms of the Akhal-Teke horses . As these two MyHC isoforms dominate in fibers with high oxidative potential (Rivero et al., 1993b; Votion et al., 2007; Leisson et al., 2008), this finding may approve the standpoint that the Akhal-Teke horses have exceptional endurance. An example of the stamina of these horses is the travel of 4300 km, from Ashkabad to Moscow (Kuznecova, 2005).
The statement that these horses possess great speed may be also explained by the relative content of MyHC isoforms in skeletal muscle. As half of the MyHC isoforms comprise IIx isoforms, which are typical for the glycolytic muscle fibers, known as the fibers with high glycolytic potential and contraction speed (Rivero, 2007; Votion et al., 2007), this may be as proof of the great speed potential of the skeletal muscles of the Akhal-Teke horses. The high percentage of the MyHC I and IIa isoform content in the skeletal muscles of the Akhal-Teke horses may indirectly explain the high resistance to muscle damage and fast repair of muscle damages of these horses. It has been previously shown that muscle fibers with high oxidative potential have higher resistance and capacity for regeneration during and after exercise (Votion et al., 2007; Seene et al., 2008 and 2009)…
The relative content of MyHC isoforms shows that the contractile apparatus of the Akhal-Teke horses has both the capacity for endurance and speed."
Read the full study here:
https://www.sciencedirect.com/science/article/pii/S1751731110002375