Nutritional Supplements Flashcards
5 nutritional supplements:
- creatine
- branched chain amino acids (BCAA)
- beta-hydroxy beta-methylbutyrate (HMbeta)
- buffers (bicarbonate, beta-alanine)
- caffeine
Creatine name:
alpha-methyl guanidine-acetic acid
Creatine is a natural substance found in the human body in:
- free form (creatine, Cr, 60-70%)
- phosphorylated form (phosphorylcreatine, PCr, 30-40%)
Both forms of creatine are ____ and ____ degraded into creatinine.
- spontaneously
- irreversibly
Creatine is excreted via the ____ with the _____.
- kidneys
- urine
Rate of creatine:
~2 g/d (~1.6% of total body stores)
Creatine is synthesized endogeneously by:
- arginine
- glycine
- methionine
- ~1-2 g/d
Ceatine can be consumed in the diet mainly from:
- meats
- fish
- dairy
- ~1-5 g/d
The amount of Cr in the human body varies depending on individual’s ___ ____.
muscle mass
Approximately ___% of the creatine content is found in ____ _____.
- 95%
- skeletal muscle
A small portion of Cr can also be found in the….
- brain
- bone
- testicles
Cr plays an important role in ____ ____ ____ during muscle contractions, specifically involving ____ , ____ ____, _____ ____.
- rapid energy provision
- high intensity
- short duration
- interval training
- ADP + PCr + Hplus = ATP + Cr
The transfer of ______ group from PCr to ADP regenerates ATP through a reversible reaction catalyzed by the enzyme ____ ____ .
- N-phosphoryl
- creatine kinase (CK)
Cr supplementation improves performance (___%) of ____ intensity, ____ duration (< ___) and, in particular, ____ activities that depend on the ___ system.
- ~10-20%
- high
- short
- < 30 s
- interval
- ATP-PCr
Cr improves performance for:
- cycling
- pole vault
- sprint running
- speed skating
- short distance swimming
- jumping
- bicycle ergometry
Potential ergogenic benefits of Cr supplementation:
- inc. single and repetitive sprint performance
- inc. work performed during sets of max effort muscle contractions
- inc. muscle mass and strength adaptations during training
- enhanced glycogen synthesis
- inc. anaerobic threshold
- possible enhancement of aerobic capacity
- inc. work capacity
- enhanced recovery
- greater training tolerance
In the short term (< 7 days) lean mass gain is related to ____ ____.
water retention (intracellular)
Cr is an ______ active substance.
osmotically
Lean mass gain is expected after ___ weeks of Cr supplementation when combined with ____.
- ~4 weeks
- RE
What happens to body comp if Cr is ingested and no exercise training is performed?
no changes in lean mass, muscle function, or bone health
There are mainly 3 Cr supplementation protocols:
- loading
- maintenance
- loading + maintenance
Loading Cr:
- 20-30 g/day for 5-7 days
- muscle is saturated after 5-7 days
Maintenance Cr:
- 5 g/d
- muscle is saturated after 4 weeks
Loading + maintenance Cr:
- 20-30 g/day for 5-7 days + 5 g/d from day 8 on
- muscle is saturated after 5-7 days and content is maintained after that
Best form of Cr:
- creatine monohydrate
- intestinal absorption ~100%
Factors that can optimize Cr muscle uptake:
- previous exercise
- carb ingestion (high GI)
Side effects of Cr:
no side effects induced by 12 weeks of creatine supplementation in older adults
The branched chain AA are 3 of the ___ EAAs.
9
BCAA ____ be produced by the body in physiologically significant amounts.
cannot
BCAAs are precursors for ____ ____ ____.
muscle protein synthesis
Widely believed claim that consumption of BCAAs:
- stimulates muscle protein synthesis
- improves endurance performance (central fatigue hypothesis)
