158 nutrition and exercise
Table 11.2
A comparison of studies on branched-chain amino acid (BCAA) supplementation in humans during endurance exercise.
Amount
Effect
Effect on performance
No. of
·Vo
2max.
of BCAA
on
subjects
Exercise
(%)
Duration (min)
ingested
p[BCAA]
NH
3
Mental
Physical
Reference
13
Cycling
40
c. 137–153
12.8 g
1250
mm
None
None
Improved
a
Mittleman
et al
. (1998)
10
Cycling
70–75
c. 122
23.4 g
2400
mm
Rise
N/M
None
b
van Hall
et al.
(1995)
Cycling
70–75
7.8 g
950
mm
Rise
N/M
None
b
van Hall
et al
. (1995)
193
c
Marathon
d
N/M
c.
>^210
16 g
1250
mm
N/M
Improved
Improved
e
Blomstrand
et al
. (1991a)
25
c
30-km run
d
5
Cycling
75
60–80
6.3 g·l
-^1
1000
mm
N/M
N/M
None
Blomstrand
et al
. (1995)
10
Cycling
72.7
50–60
16 g·day
- 1g
N/M
N/M
N/M
Improved
Hefler
et al
. (1995)
7
Cycling
65–75
c. 30
30 g
3000
mm
Rise
N/M
None
Wagenmakers (1992)
6
Soccer
d
N/M
10 g
f
1200
mm
N/M
Improved
N/M
Blomstrand
et al
. (1991b)
52
30-km run
d
N/M
145
5.3 g
h
650
mm
N/M
Improved
N/M
Hassmen
et al
. (1994)
10
Cycling
70
c. 230
0.74 g·l
- 1f
420
mm
N/M
N/M
None
Galiano
et al
. (1991)
7
Cycling
70
60
6–9 g
1050
mm
None
Improved
Improved
Blomstrand
et al
. (1997)
9
Cycling
i
63.1
c. 159
18 g
j
1026
mm
Rise
N/M
None
Madsen
et al
. (1996)
10
Cycling
N/M
c. 125–212
21 g
c.1250
mm
Rise
Improved
None
Struder
et al
. (1998)
N/M, not measured; p[BCAA], the peak plasma concentration of branched-chain amino acids observed in each study.aSubjects experienced heat stress. bVery high day-to-day intraindividual variation in time to fatigue for some subjects.cNot all subjects gave blood samples.dField study.eIn subset of slower runners.f6% carbohydrate added.g14-day study.h7% carbohydrate added.i100-km trials.j5% carbohydrate added.