A few days ago I was getting myself into my pre-workout ‘jacked’ phase having consumed a protein/carbohydrate supplement with some added leucine about an hour earlier when I started noticed a couple of the younger gym rats drinking Power-Aid.  It hit me then, I felt like Jessie Ventura in "Predator" when Arnold goes and picks up the truck and Jessie says, "What the fuck?" I was kind of shocked that the word still has not got out that carbohydrate drinks by themselves without some added amino acids is really settling for less in our quest for muscle growth. 

Why the hell are lifters drinking Power-Aid?

Carb Drinks Do Not Increase Resistance Exercise Performance

Surely, the word hasten out that consuming a carbohydrate beverage alone is not going to do anything for increasing protein synthesis and creating an anabolic drive for muscle hypertrophy.  Sure, all those Gatorade and Power-Aid commercials look cool with the neo colors coming out of their pores, but its not going to do a hell of a lot for you in the gym.  Won't drinking a carbohydrate drink increase your maximal strength and reduce fatigue in the gym? 

Researchers studied whether drinking a carbohydrate drink may reduce perceptional effort in the gym.  Thirty strength-trained subjects were randomized to a carbohydrate group (C) or a placebo group (P), and lifted weights for 2 hours (4 sets; 10 repetitions maximum; 10 exercises; 2-3-minute rest intervals). Subjects ingested 10 ml/ kg/hour of 6% carbohydrate or placebo beverages during the resistance-training bout. The 15-category Borg Perceived Exertion Scale was used to assess overall body exertion after completion of the last repetition in each set for each exercise. Carbohydrate supplementation exerted no attenuating effect on ratings of perceived exertion (RPE) during resistance training (19). Basically, it means the group drinking carbohydrate beverages didn't find the workouts any easier than the group drinking water.  

But drinking some extra carbs should help improve performance with regards to high intensity repetitive sessions in the gym right?  According to a new 2006 study in the Journal of Strength and Conditioning Research, it does not matter whether you consume a high or low carb diet; it's not going to do a lot for performance in the gym.  In that study, multiple sets of jump squats were performed by men consuming either a high-CHO (6.5 g CHO kg body mass) diet compared to a moderate-CHO (4.4 g CHO kg body mass) diet. The resistance exercise test consisted of 4 sets of 12 repetitions of maximal-effort jump squats using a Plyometric Power System unit and a load of 30% of 1 repetition maximum (1RM). A 2-minute rest period was used between sets. The results indicated that the power output during multiple sets of maximal jump squats was not enhanced following a higher-CHO diet compared to a moderate- or lower-CHO diet. These data show that elevated carbohydrate intake is not needed to optimize a repetitive power-performance (17).

Some studies suggest that drinking a carbohydrate beverage during exercise may help reduce cortisol and reduce oxidative stress, but not all studies have reported this. McAnulty et al.18  had thirty strength-trained subjects consume either a carbohydrate (CHO) beverage or placebo (PLA) groups that lifted weights for 2 h. Subjects received 10 ml kg per hr. CHO (6%) or PLA beverages during the exercise. Blood and vastus lateralis muscle biopsy samples were collected before and after exercise and analyzed for cortisol as a marker of general stress, F(2)-isoprostanes as a measure of oxidative stress. Interestingly, the study found that decreases in muscle glycogen content did not differ between CHO and PLA. Cortisol increased significantly in CHO and PLA, but the pattern of change was not different between groups. F(2)-isoprostanes were unaffected by exercise. These results indicate that exhaustive resistance exercise and carbohydrate ingestion have no effect on oxidative stress and cortisol in trained resistance trained subjects.  

Do carbohydrate drinks help out with anything?  Carbohydrates supplements do reduce muscle protein breakdown but have no effect on muscle protein synthesis (1, 2).  In fact, even though carbohydrate ingestion alone reduced muscle tissue breakdown, the net balance protein kinetics still remains negative (15). Going to the gym and drinking a carbohydrate beverage is not supporting optimal anabolic activity for muscle growth. In a way, its does have some effect, but why half-ass it…why fill up on carbs and extra calories?  Additionally, carbohydrate ingestion during exercise results in a decrease in the expression of genes involved in fatty acid transport and oxidation (carnitine palmitoyltransferase-1, uncoupling protein 3) (6).

Although the bottles look cool… carbohydrate ingestion during exercise results in a decrease in the expression of genes involved in fatty acid transport and oxidation (carnitine palmitoyltransferase-1, uncoupling protein 3) and has no effect on increasing protein synthesis.