Effects of sweetness and energy in drinks on food intake following exercise

Exercise is known to cause physiological changes that could affect the impa ct of nutrients on appetite control. This study was designed to assess the effect of drinks containing either sucrose or high-intensity sweeteners on food intake following exercise. Using a repeated-measures design, three dri nk conditions were employed: plain water (W), a low-energy drink sweetened with artificial sweeteners aspartame and ace-sulfame-K (L), and a high-ener gy, sucrose-sweetened drink (H). Following a period of challenging exercise (70% VO2 max for 50 min), subjects consumed freely from a particular drink before being offered a test meal at which energy and nutrient intakes were measured. The degree of pleasantness (palatability) of the drinks was also measured before and after exercise. At the test meal, energy intake follow ing the artificially sweetened (L) drink was significantly greater than aft er water and the sucrose (H) drinks (p < 0.05). Compared with the artificia lly sweetened (L) drink, the high-energy (H) drink suppressed intake by app roximately the energy contained in the drink itself. However, there was no difference between the water (W) and the sucrose (H) drink on test meal ene rgy intake. When the net effects were compared (i.e., drink + test meal ene rgy intake), total energy intake was significantly lower after the water (W ) drink compared with the two sweet (L and H) drinks. The exercise period b rought about changes in the perceived pleasantness of the water, but had no effect on either of the sweet drinks. The remarkably precise energy compen sation demonstrated after the higher energy sucrose drink suggests that exe rcise may prime the system to respond sensitively to nutritional manipulati ons. The results may also have implications for the effect on short-term ap petite control of different types of drinks used to quench thirst during an d after exercise. (C) 1999 Elsevier Science Inc.