Although further evidence would help support supplementation
with glutamine to an even higher degree, there is considerable
research to warrant its usage among many high performance athletes.
The benefits as previously noted includes: supporting a healthy
immune system, less reduction in body and muscle weights, lower
myostatin expression, increased levels of growth hormone, decreased
catabolic effects of skeletal muscle, increased anabolic effects,
increased protein synthesis, and greater ability to sustain high
intensity exercise due to the increased capability of buffering
lactic acid. All these factors could potentially lead to increases
in muscle mass, strength, and power.
The recommended dosage for glutamine is 5-20 grams per day. There
are claims that even higher dosages may be more effective, but
further evidence is needed. However, there have been studies
demonstrating that 40 grams a day has no safety or toxicity concerns.
Therefore, toxicity is not an issue with glutamine supplementation.
Distributing glutamine throughout the day in smaller dosages
is also recommended. A common glutamine supplementation protocol
is 5 grams in the morning, 5 grams pre-workout, followed by 5
grams post workout, with an optional 2-5 gram dosage before bed.
Similar guidelines and dosage amounts are recommended for non-workout
According to consumerlab.com and other valid sources, some of
the best glutamine products on the market include: Dymatize Proline
Micronized Glutamine, Effervescent Glutamine, Puritan's Pride
L-Glutamine, AST Glutamine, Beverly International Glutamine Select
Plus BCAAs, and Precision Engineered Pure L-Glutamine.
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