(I plan to add to this post as I do more research. This is the brief beginning.)
Yoga, depending on the practice, can be meditation in movement while also releasing the anti-depressant and anti-anxiety gamma-amino butyric acid (GABA) (Streeter, C. C., Whitfield, T. H., Owen, L., Rein, T., Karri, S. K., Yakhkind, A., . . . Jensen, J. E., 2010). Tai chi reportedly increases muscle strength, flexibility, balance, as well as aerobic conditioning (“The health benefits of tai chi”, n.d.)
Energy systems, muscle fiber use, muscle action
Strength training systems at work
The energy systems for strength training depend on direct phosphorylation for the first 5 to 15 seconds, the energy source being creatine phosphate with no oxygen and producing adenosine triphosphate (ATP). Mostly, the strength training uses the anaerobic or glycolytic pathway, using glucose, no oxygen, and produces double the ATP, or 2 ATP per glucose, and last about 30 to 40 seconds (Rivera-Brown, A. M., & Frontera, W. R., 2012). Strength training uses gross motor movement and Type IIb/x muscles. Finally, the muscle action is concentric (isotonic), shortening, working against the force, and eccentric (isotonic), lengthening and also working against the force.
Yoga and tai chi for flexibility, balance, and strength
Yoga and tai chi provide a lot of benefits in strength, flexibility, balance, and aerobic conditioning as well as neurological benefits from the creation of GABA (Streeter, C. C., et al, 2010, “The health benefits of tai chi”, n.d.). Because aśtanga and hatha yoga, which is more like “power yoga” and does strengthen muscles, the first few seconds requires direct phosphorylation, uses the anaerobic (glycolytic) pathway during the hardest flowing asanas and, finally, due to the focused breathing and flowing motion accesses the oxidative aerobic pathway, using glucose, pyruvic acid, free fatty acids from adipose tissue, and amino acids from protein catabolism which allows the hatha/power yoga and tai chi practitioner to practice for hours. The aerobic pathway exercise produces 32 ATP per glucose, as well as carbon dioxide (C02) and water (H20) (Pojednic, R., Feb 16, 2016. Personal communication). Tai chi may not use the anaerobic pathway much as it is a flowing movement, but the state of constant balance required relies on some anaerobic strengthening. Yoga and tai chi use fine motor movement and slow twitch, Type I, muscle fibers particularly due to the use of postural muscles with the exception of the hatha/power asanas, which use both fine motor and gross motor movement and Type IIa or b fibers.
The muscle action in yoga and tai chi includes all three types: concentric (isotonic), shortening, working against the force, static (isometric) when poses are held, and eccentric (isotonic), lengthening and also working against the force.
All of the training will rely on agonist, antagonist, and synergist types of muscles although the asanas in yoga and balance in tai chi may require extra input from the antagonist muscles.
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References
Yoga – Benefits Beyond the Mat - Harvard Health. (n.d.). Retrieved February 22, 2016, from http://www.health.harvard.edu/staying-healthy/yoga-benefits-beyond-the-mat
Woodyard, C. (2011). Exploring the therapeutic effects of yoga and its ability to increase quality of life. International Journal of Yoga Int J Yoga, 4(2), 49.
Streeter, C. C., Whitfield, T. H., Owen, L., Rein, T., Karri, S. K., Yakhkind, A., . . . Jensen, J. E. (2010). Effects of Yoga Versus Walking on Mood, Anxiety, and Brain GABA Levels: A Randomized Controlled MRS Study. The Journal of Alternative and Complementary Medicine, 16(11), 1145-1152.
The health benefits of tai chi - Harvard Health. (n.d.). Retrieved February 22, 2016, from http://www.health.harvard.edu/staying-healthy/the-health-benefits-of-tai-chi
Rivera-Brown, A. M., & Frontera, W. R. (2012). Principles of Exercise Physiology: Responses to Acute Exercise and Long-term Adaptations to Training. Pm&r, 4(11), 797-804.