Unformatted text preview: r does not produce an anabolic effect
on skeletal muscle that is independent of the quality
and quantity of the exercise stimulus.
Another study that failed to support the use of Cr
was conducted by Tarnopolsky et al. who
randomised 19 male subjects into either a Cr +
carbohydrate group (n = 11; 10g Cr + 75g glucose)
or protein + carbohydrate group (n = 8; 10g casein +
75g glucose) in a double-blind design. Prior to treatments, subjects were tested using 16 separate 1RM
tests to assess isoinertial strength. Resistance training focused on training the whole body over a 6-day
week in a split routine design. Training sessions
lasted 1 hour for a total of 8 weeks. The results
indicated that 1RM strength, in all 16 exercises,
increased post-training (ranging from 14.2% to 2005 Adis Data Information BV. All rights reserved. Bemben & Lamont 39.9%) but there were no significant differences
between the two groups. Strength gains may have
been similar for both conditions due to increased
protein synthesis (resistance training plus Cr) or
increased protein availability post-exercise (resistance training plus protein). It should be noted that
this study used great care to ensure that both supplements provided the same energy content, a criticism
of many Cr supplementation studies.
2.1.2 Isokinetic Peak Torque The effect of Cr loading on measures of isokinetic performance are more controversial than for measures of dynamic or isoinertial maximal force. Rossouw et al. conducted a study using 13 highly
trained strength athletes to examine the effects of
acute Cr supplementation on isokinetic peak torque.
Subjects were randomly assigned to either a Cr
group (n = 8; 9g, three times daily) or a placebo
group (n = 5) for 5 days of treatment. Subjects were
required to perform three sets of 25 consecutive,
maximal concentric knee extensions at 180 degrees/
second with 60 seconds recovery between sets.
Paired t-tests indicated mixed results, with both
groups having significant increases in peak torque
for exercise bout two, but only the Cr group had a
significant increase in bout three. The improvement
in more of th...
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