wat te eten voor cardio
What To Eat Before Cardio
One dilemma facing athletes is whether to eat anything before cardio, and if so, what. A recent study sheds some light on this and suggests the best option. (1).
The rationale for cardio on an empty stomach is obviously to increase fat burning. When carbs are taken in before exercise the carbs are preferentially used for fuel, sparing fat. On the other hand exercising on an empty stomach elevates cortisol levels which break down not only fats but muscle for fuel.
The other option is ingesting protein before exercise. This may spare muscle, but does it inhibit fat burning? Surprisingly, according to the study, it depends on the type of protein.
Rats were exercised under 4 different conditions. (1) Fasting. (2) Glucose meal before exercise. (3) whole milk protein before exercise (4) lactalbumin enriched whey before exercise.
At the end of the study, the glucose and milk protein fed rats gained fat mass, showing that these diets blunted the fat burning from exercise. The fasted rats lost both muscle and fat, whereas the whey fed rats lost just as much fat as the fasted rats, but gained muscle.
The moral is to burn fat and actually build muscle while doing cardio, ingest whey protein beforehand.
Am J Physiol Endocrinol Metab 2002 Sep;283(3):E565-72
A preexercise alpha-lactalbumin-enriched whey protein meal preserves lipid oxidation and decreases adiposity in rats.
Bouthegourd JC, Roseau SM, Makarios-Lahham L, Leruyet PM, Tome DG, Even PC.
Unite Mixte de recherche de Physiologie de la Nutrition et du comportement alimentaire, Institut National de la Recherche Agronomique, Institut National Agronomique Paris-Grignon, F75231 Paris, France.
The composition of the preexercise food intake is known to affect substrate utilization during exercise and thus can affect long-term changes in body weight and composition. These parameters were measured in male rats exercised 2 h daily over 5 wk, either in the fasting state or 1 h after they ingested a meal enriched with glucose (Glc), whole milk protein (WMP), or alpha-lactalbumin-enriched whey protein (CPalphaL). Compared with fasting, the Glc meal increased glucose oxidation and decreased lipid oxidation during and after exercise. In contrast, the WMP and CPalphaL meals preserved lipid oxidation and increased protein oxidation, the CPalphaL meal increasing protein oxidation more than the WMP meal. At the end of the study, body weight was larger in the WMP-, Glc-, and CPalphaL-fed rats than in the fasted ones. This resulted from an increased fat mass in the WMP and Glc rats and to an increased lean body mass, particularly muscles, in the CPalphaL rats. We conclude that the potential of the CPalphaL meal to preserve lipid oxidation and to rapidly deliver amino acids for use during exercise improved the efficiency of exercise training to decrease adiposity.