Hopefully This Week’s Blog will Get You “Pumped Up”!
This week’s blog focuses on the global effects that exercise aimed at increasing lean body mass (muscle tissue) can have on preventing and reversing diseases, facilitating weight loss and promoting longevity.
In general, skeletal muscle consists of two types of fibers. Type I (slow oxidative/slow twitch) and type II (fast glycolytic/fast twitch).
The slow twitch fibers (I) use aerobic metabolism for continuous, extended muscle contractions over a longer periods of time. Slow twitch fibers are great for endurance activities such as marathons and Triathlons due to their concentration of mitochondria and resistance to fatigue.
Fast twitch fibers (II) use anaerobic metabolism for generating short bursts ideal for strength or speed. These fibers help a sprinter generate a lot of speed or a weight lifter produce forceful and powerful movements.
Researchers have demonstrated that an increase in type II fibers in the form of lean body/muscle mass can reduce body fat and increase whole body metabolism which in turn reduces overall body mass and improves metabolic parameters such as insulin resistance.
In addition, resistance training programs that are designed to increase skeletal muscle mass are effective strategies in the fight against obesity and obesity-related comorbidities including diabetes, heart disease, stroke, hypertension, and cancer.
Anti-aging and anti-inflammatory benefits
Resistance exercise can prevent the degenerative processes and inflammation associated with ageing through the production of anti-inflammatory cytokines (substances, secreted the immune system and have an effect on other cells), along with a reduction of pro-inflammatory cytokines.
Periodized resistance training seems to be an important intervention to reduce systemic inflammation, the underlying cause of most chronic diseases.
(Prestes et al. 2009)
Myokines (muscle cytokines) are secreted from skeletal muscles in response to exercise. These function as hormones either locally within the muscle or by targeting distant organs.
During and after exercise, myokines stimulate a cross talk between skeletal muscles and other organs. This results in fatty acid oxidation along with a reduction in adipose tissue (fat).
Myokines. e.g IL-6, IL-8 and IL-15, play an important role in mediating whole-body adaptive effects of exercise through the regulation of skeletal muscle metabolism.
In addition, they also contribute to whole-body metabolism through signaling to distant organs and regulating metabolic processes in liver and adipose tissue.
Myokines play an important role in restoring a healthy cellular environment by reducing low-grade inflammation and preventing metabolic related diseases like insulin resistance and cancer.
Skeletal muscle is recognized as an endocrine organ that produces and releases myokines which in turn influences the nervous, endocrine, and immune systems and contributes to the maintenance of homeostasis.
Given that skeletal muscle is the largest organ in the human body, exercise that stimulates muscle contraction can have an enormous influence on metabolism and other tissues and organs. In this regard, resistance training has been shown to have profound local and hormonal effects as mentioned above.
Moderate intensity and Myokines
The effect of resistance exercise on blood myokines and angiogenesis varies according to the intensity. Moderate intensity resistance training has been shown to be the most effective at increasing myokines due to continuous muscle contractions.
(Yeo et al., 2012)
OPT- Phase III- Hypertrophy Training
Hypertrophy training adaptations ultimately result in maximal muscle growth. Current evidence suggest that the acute variables should emphasize high volume with minimal rest periods.
|Acute variables/Adaptation||Reps||Sets||Tempo||% Intensity||Rest Interval||Frequency||Duration||Exercise Selection|
|Hypertrophy||6-12||3-5||2-0-2||75-85%||0-60 s||3-6x/week||4 weeks||2-4 strength level exercises/body part*|
- Compound movements such as squats, dead lifts, lunges, bench press, shoulder press, pull-ups and rowing have a significant influence on muscle metabolism.
High Intensity Interval Training (HIIT)- The icing on the cake
High intensity exercise using short burst of all out effort, creates a hormonal environment that produces sustained fat burning as well as muscle growth (Type II muscle fibers ).
In addition, HIIT increases IL-6 and catecholamines, which work synergistically to reduce inflammation.
(Croft, 2009) (Yusuke, 2014)
Exercise focusing on muscle growth (resistance training and HIIT) produces myokines.
Myokines are involved in mitigating low-grade inflammation and impaired metabolism.
By strategically manipulating the acute variables of exercise to promote an increase in lean body mass, exercise can be used to prevent and manage many of the common illnesses we are faced with today.
Clark, M., Lucett, S., Corn, R. . NASM Essentials of Personal Fitness Training. Baltimore: LWW, 2008
Croft, Louise; Bartlett, Jonathan D.; MacLaren, Don P. M.; Reilly, Thomas; Evans, Louise; Mattey, Derek L.; Nixon, Nicola B.; Drust, Barry; Morton, James P.
High-intensity interval training attenuates the exercise-induced increase in plasma IL-6 in response to acute exercise. Applied Physiology, Nutrition & Metabolism Dec2009, Vol. 34 Issue 6, p1098
Pedersen, Line and Hojman, Pernille. Muscle-to-organ cross talk mediated by myokines. Adipocyte. 2012 Jul 1; 1(3): 164–167.
Pedersen, B, Thorbjörn, Åkerström, CA, Nielsen, A and Fischer, C. Role of myokines in exercise and metabolism. J Appl Physiol 103: 1093–1098, 2007
Prestes J, Shiguemoto G, Botero JP, Frollini A, Dias R, Leite R, Pereira G, Magosso R, Baldissera V, Cavaglieri C, Perez S. Effects of resistance training on resistin, leptin, cytokines, and muscle force in elderly post-menopausal women. J Sports Sci. 2009 Dec;27(14):1607-15. doi: 10.1080/02640410903352923. http://www.ncbi.nlm.nih.gov/pubmed/19967592
Yeo NH, Woo J, Shin KO, Park JY, Kang S. The effects of different exercise intensity on myokine and angiogenesis factors. J Sports Med Phys Fitness. 2012 Aug;52(4):448-54.
Yusuke Osawa; Koichiro Azuma; ShogoTabata; Fuminori Katsukawa; Hiroyuki Ishida; Yuko Oguma; Toshihide Kawai; Hiroshi Itoh; Shigeo Okuda; Hideo Matsumoto. Effects of 16-week high-intensity interval training using upper and lower body ergometers on aerobic fitness and morphological changes in healthy men: a preliminary study Open Access Journal of Sports Medicine 2014, Vol. 5, p257