NUTRITION IN SPORT

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.