Small amount of BCAAs and L-arginine prevents cardio-induced muscle breakdown
A cardio session - especially when done after strength training - has lots of positive health effects, but cardio exercise breaks down muscle tissue. For strength athletes cardio is a double-edged sword. Researchers at Otsuka Pharmaceutical in Japan think you can make one side of the sword less sharp by taking 2 g BCAAs and 0.5 g arginine.
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Study
High doses of BCAAs reduce muscle breakdown during physical exercise and boost the body's anabolic response. The researchers wanted to know whether lower doses of BCAAs supplemented with a small amount of L-arginine might do the trick as well.The Japanese did an experiment with 4 men and 4 women, all of whom were healthy, in their mid-twenties and untrained. The subjects were given breakfast, after which they had to cycle three times for 20 minutes at 50 percent of their maximal intensity. They rested for 5 minutes between each session.
Ten minutes after starting this anything but intensive workout, the subjects took their amino acids, dissolved in a sports drink. The method of administration gives an indication of the researchers' intentions. Then the researchers repeated the experiment, but gave the subjects a placebo.
The researchers measured the amount of amino acids that the subjects absorbed and excreted during the workout via a catheter inserted into the leg. The more amino acids released from leg muscles, the greater the muscle breakdown, the researchers reasoned.
Results
The tables below show the net effect: the uptake of amino acids in the leg muscles minus the release. As you can see, supplementation reduced the release of glutamine and alanine.
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The effect was greatest at the end of the workout - during the third session. The figures are for phenylalanine.
If you look at phenylalanine, the mix of BCAAs and L-arginine blocks muscle breakdown almost completely during the third workout.
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Conclusion
The anticatabolic effect of the amino acid-laced sports drink would probably have been greater if the test subjects hadn't drunk it during the workout but beforehand. Higher doses would undoubtedly have had a greater anticatabolic effect.
The research results suggest a strategy that could well give strength athletes more benefit from doing cardio after their weight training: take a dose of BCAAs and L-arginine before getting on the treadmill.
Source:
Int J Sports Med. 2007 Jun;28(6):531-8.
A cardio session - especially when done after strength training - has lots of positive health effects, but cardio exercise breaks down muscle tissue. For strength athletes cardio is a double-edged sword. Researchers at Otsuka Pharmaceutical in Japan think you can make one side of the sword less sharp by taking 2 g BCAAs and 0.5 g arginine.
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Study
Iso-Leucine 
Valine |
Ten minutes after starting this anything but intensive workout, the subjects took their amino acids, dissolved in a sports drink. The method of administration gives an indication of the researchers' intentions. Then the researchers repeated the experiment, but gave the subjects a placebo.
The researchers measured the amount of amino acids that the subjects absorbed and excreted during the workout via a catheter inserted into the leg. The more amino acids released from leg muscles, the greater the muscle breakdown, the researchers reasoned.
Results
The tables below show the net effect: the uptake of amino acids in the leg muscles minus the release. As you can see, supplementation reduced the release of glutamine and alanine.
[FONT="]
[/FONT]
[FONT="]
[/FONT]
The effect was greatest at the end of the workout - during the third session. The figures are for phenylalanine.
If you look at phenylalanine, the mix of BCAAs and L-arginine blocks muscle breakdown almost completely during the third workout.
[FONT="]
[/FONT]
[FONT="]
[/FONT]
Conclusion
The anticatabolic effect of the amino acid-laced sports drink would probably have been greater if the test subjects hadn't drunk it during the workout but beforehand. Higher doses would undoubtedly have had a greater anticatabolic effect.
The research results suggest a strategy that could well give strength athletes more benefit from doing cardio after their weight training: take a dose of BCAAs and L-arginine before getting on the treadmill.
Source:
Int J Sports Med. 2007 Jun;28(6):531-8.