Physical Endurance and Muscle Recovery
Work, Sport, Leisure – in fact all physical activity will generate reactive oxygen species (ROS); the more intense the activity the greater number of free radicals. ROS are shown to have damaging effects on muscle performance and recovery. Published and on-going research, focused on improving endurance and reducing recovery time, are showing dramatic benefits linked to the potent carotenoid - astaxanthin. These findings are bringing astaxanthin to the forefront as a dietary supplement for professional athletes and physically active people.
Important to physical activity are our mitochondrial cells, often referred to as the “power stations of the cell” , which provide as much as 95% of our body’s pure energy (primarily by the burning of muscle glycogen and fatty acids). Unfortunately, a portion of this energy produces highly reactive and damaging ROS. ROS damage cells by triggering peroxidation of the cell membrane components, and oxidation of DNA and proteins. Furthermore, ROS continue to affect muscles even after the strenuous exercise has ceased. ROS activate the inflammation response whereby monocytes migrate into the muscle tissue causing additional cell damage. Often we will notice the onset of muscle damage during recovery in the form of tiredness and soreness. In addition to improving muscle performance through devised exercise regime, the sports research community is looking at other methods, such as nutrition to fuel and protect the body under extreme physical conditions. In the past, Vitamins E and C helped make the use of antioxidants a popular tool against oxidative damage during intense physical activity. Today, informed by current research we can point to astaxanthin as the antioxidant of choice for sports performance. Astaxanthin demonstrated 3 important physical benefits in clinical trials and supporting studies. Astaxanthin increased endurance, reduced muscle damage and improved lipid metabolism.
Astaxanthin Boosts EnduranceIn a randomized, double-blind, placebo controlled study on healthy men supplemented with 4 mg astaxanthin per day for up to 6 months at Karolinska Institute, Sweden, standardized exercise tests demonstrated that the average number of knee bends performed increased only in the astaxanthin treated group at 3 months, and by the 6 month significant improvements were observed (Figure 1) (Malmsten & Lignell, 2008).
Figure 1. Increase in strength/endurance (Malmsten & Lignell, 2008)
Figure 2. Effect of astaxanthin on swimming time (Ikeuchi et al., 2006)
Figure 3. Reduction of lactic acid build-up after astaxanthin supplementation in track subjects (Sawaki et al., 2002)
Figure 4. Effect of astaxanthin on blood lactate during swimming for 15 minutes (Ikeuchi et al., 2006)
The MechanismThe mechanism behind muscle endurance is based on several findings. Generally, astaxanthin protected the skeletal muscle from the increased damage of oxidative stress generated by physical activity. Furthermore, astaxanthin increased the metabolism of lipids as the main source of energy production by protecting the carnitine palmitoyltransferase I (CPT I) involved in fatty acid transport into mitochondria. Aoi et al., (2003) of Kyoto Prefecture University used mice models that may partially explain the efficacy of astaxanthin; they compared control, exercise placebo, and astaxanthin treated exercise groups after intense physical activity. 4-hydroxy-2-nonenal-modified-protein (4-HNE) stain analyses of the calf (gastrocnemius) muscles revealed significantly lower peroxidation damage (Figure 5).
Figure 5. Effect of astaxanthin on 4-HNE-modifed proteins in leg muscle before and after exercise (Aoi et al., 2003)Other biochemical markers for oxidative damage and inflammation such as DNA, (2003) also explained that astaxanthin directly modulates inflammation caused by the release of the pro-inflammatory cytokines and mediators. In vivo and in vitro tests demonstrate that astaxanthin inhibits the IκB Kinase (IKK) dependant activation of the Nuclear Factor-kB (NF-κB) pathway, a key step in the production of pro-inflammatory cytokines and mediators. Aoi et al., 2008 also demonstrated increased lipid metabolism compared to carbohydrate as the main source of energy during strenuous activity (Figure 6). Furthermore, analysis of the mitochondrial lipid transport enzyme known as carnitine palmitoyltransferase I (CPT I) revealed increased fat localization (Figure 7) and reduction of oxidative damage in the presence of astaxanthin (Figure 8). CPT I is important because it regulates fatty acyl-CoA entry into the mitochondria in the oxidation of fatty acids in muscle. Exercise-induced ROS may partly limit utilization of fatty acid via diminishing CPT I activity.
Figure 6. Fat substrate utilization increased with astaxanthin (Aoi et al., 2008)
Figure 7. Increased amount of FAT/CD36 that coimmunoprecipitated with CPT I skeletal muscle after a single session of exercise at 30 m/min for 30 min (Aoi et al., 2008)
Figure 8. Astaxanthin reduced the amount of HEL-modified CPT1 in skeletal muscle after a single session of exercise at 30m/min for 30min (Aoi et al., 2008)
Strenuous physical activity generates high levels of ROS which affect muscle performance and metabolism of lipids. New research shows that astaxanthin can modify muscle metabolism via its antioxidant effect, resulting in the improvement of muscle function during exercise. Therefore, astaxanthin is expected to be useful for physically active people as well as athletes.
- Aoi W, Naito Y, Sakuma K, Kuchide M, Tokuda H, Maoka T, Toyokuni S, Oka S, Yasuhara M, Yoshikawa T. (2003). Astaxanthin limits exercise-induced skeletal and cardiac muscle damage in mice. Antioxid Redox Signal, 5(1):139-144.
- Aoi W, Naito Y, Takanami Y, Ishii T, Kawai Y, Akagiri S, Kato Y, Osawa T, Yoshikawa T. (2008). Astaxanthin improves muscle lipid metabolism in exercise via inhibitory effect of oxidative CPT I modification. Biochem. Biophys. Res. Com., 366:892–897.
- Fukamauchi, M. (2007). Food Functionality of astaxanthin-10: Synergistic effects of astaxanthin-10 intake and aerobic exercise. Food Style 21, 11(10). [In Japanese]
- Ikeuchi M, Koyama T, Takahashi J, Yazawa K. (2006). Effects of astaxanthin supplementation on exercise-induced fatigue in mice. Bio. Pharm. Bull., 29(10):2106-2110.
- Lee SJ, Bai SK, Lee KS, Namkoong S, Na HJ, Ha KS, Han JA, Yim SV, Chang K, Kwon YG, Lee SK, Kim YM. (2003). Astaxanthin Inhibits Nitric Oxide Production and Inflammatory Gene Expression by Suppressing IκB Kinase-dependent NF-κB Activation. Mol. Cells, 16(1):97-105.
- Malmsten C, Lignell A. (2008). Dietary supplementation with astaxanthin rich algal meal improves muscle endurance – a double blind study on male students. Carotenoid Science 13:20-22.
- Sawaki K, Yoshigi H, Aoki K, Koikawa N, Azumane A, Kaneko K, Yamaguchi M. (2002). Sports performance benefits from taking natural astaxanthin characterized by visual activity and muscle fatigue improvements in humans. J Clin.Therap. Med., 18(9):73- 88.
CCRES special thanks to
Mr. Mitsunori Nishida,
President of Corporate Fuji Chemical Industry Co., Ltd.
Croatian Center of Renewable Energy Sources (CCRES)