NUTRITION IN SPORT

early investigations showing the importance of
adequate fluid replacement during prolonged
exercise in the heat. In fact, the earliest reference
to fluid replacement during long-distance
running is found in the 1953 International

554 sport-specific nutrition

Amateur Athletic Federation (IAAF) Handbook

controlling marathon events. The handbook

stated that ‘refreshments shall only be provided

by the organizers of a race after 15 km’, and that

‘no refreshments could be carried or taken by a

Table 42.4Effects of carbohydrate loading on prolonged running lasting longer than 90 min. Adapted from
Hawleyet al. (1997b).

Muscle glycogen
(mmol · kg-^1 wet weight)
Performance
Dietary treatment Pre-exercise Postexercise measure Results

A: 4 days LCHO (10.5% CHO, 76% fat, A: 45± 19 A: 35± 21 Run to A: 64±16 min (n=7M)
13.5% protein) exhaustion at
B: 4 days HCHO (77% CHO, 13.5% protein, B: 112± 61 B: 75± 19 70% V

.

o2max B: 106±13 min

9.5% fat)

A: NORM ——Run to A Trial 1: 119±19 min
Trial 1: 4.6±1.3g·kg-^1 BM CHO · day-^1 exhaustion at (n=15 M, 15 F)
Trial 2: 5.1±1.4 70% V
.
o2max Trial 2: 122±22 min
B: COMPLEX CHO B Trial 1: 106±24 min
Trial 1: 4.6±1.3g·kg-^1 BM CHO · day-^1 Trial 2: 133±46 min
Trial 2: 7.7±1.8
C: SIMPLE CHO C Trial 1: 114±16 min
Trial 1: 4.0±0.7g·kg-^1 BM CHO · day-^1 Trial 2: 141±27 min
Trial 2: 7.0±1.2

A: 3.5 days 6.1 g · kg-^1 BM CHO · day-^1 (pasta) A: 103± 49 — Run to A: 153±49 min (n=14 M)
B: 3 days 2.4 g · kg-^1 BM CHO · day-^1 and B: 130± 47 exhaustion at B: 169±30 min
depletion exercise, then 3.5 days 75% V

.
o2max
11.2g·kg-^1 BM CHO · day-^1 (pasta)
C: 3.5 days 6.3 g · kg-^1 BM CHO · day-^1 C: 107± 32 C: 139±26 min
(beverage)
D: 3 days 2.5 g · kg-^1 BM CHO · day-^1 and D: 150± 44 D: 168±27 min†
depletion exercise, then 3.5 days
11.6g·kg-^1 BM CHO · day-^1 (beverage)

A: NORM A: 100± 39 A: 29± 33 30-km A: 143±20 min (n=10 M)
B: HCHO—3 days no CHO, then 3 days B: 194± 66 B: 105± 72 running race B: 135.3±18 min
9g·kg-^1 BM CHO · day-^1

A: NORM ——30-km A: Trial 1: 135.3±14.1 min
Trial 1: 5±1g·kg-^1 BM CHO · day-^1 treadmill run (n=12 M, 6 F)
Trial 2: 7 days 5.4±0.8 Trial 2: 135.3±14.1 min
B: HCHO B: Trial 1: 137.5±16.5 min
Trial 1: 5.1±0.8g·kg-^1 BM CHO · day-^1 Trial 2: 134.9±16.5 min‡
Trial 2: 3 days 8.6±1.3
4 days 6.9±1.2

BM, body mass; F, female; HCHO, high carbohydrate intake; LCHO, low carbohydrate intake; M, male; NORM, normal
diet; 1 mmol · kg-^1 wet weight=4.3 mmol · kg-^1 dry weight.
All values are mean±SD.
*B 2 >B 1 , C 2 >C 1 (P<0.01).
†D>C (P<0.05).
‡ 1.9% improvement; increase in speed over last 5 km during Trial 2 (P<0.001).