It doesn’t really make an awful lot of difference which easily absorbable carbohydrates strength athletes use for their protein shakes. According to a 2007 American study, all types of fast carbs have pretty much the same effect on insulin, glucose, testosterone and cortisol levels. But if you have to choose one that works best, then it would be honey.
Study
If you are one of those people who hardly every puts on weight and can therefore afford to put carbohydrates in their protein shake, then you may be interested in an article that Richard Kreider published in 2007 in the Journal of the International Society of Sports Nutrition. In his study Kreider got 40 well trained strength athletes to do a full body workout after which they drank a shake containing whey.
The shake contained 40 g whey and 120 g of an easily digested carbohydrate: sucrose [ordinary sugar], maltodextrin or honey. The honey that the researchers used consisted of 31 percent glucose, 25 percent wheat starch, 13 percent insoluble fibre and 5 percent of maltose. The researchers also gave the subjects no shake at all on one occasion.
Results
For a period of two hours after the workout and consuming the shake the researchers monitored the subjects’ blood. They observed no statistically significant effects on the testosterone and cortisol levels.
The effect on the insulin level is shown below: all three carbohydrates have virtually the same effect.
The figure above shows the effect of the three carbohydrates on the glucose level. Once again, all three carbohydrates perform approximately the same – but honey performs a tiny bit better than the other products. Click on the figure for a larger version.
Conclusion
“Although ingesting honey as the source of carbohydrate with protein tended to maintain blood glucose levels to a greater degree, no significant differences were observed among the types of carbohydrate ingested in terms of insulin response to supplementation”, the researchers wrote.
“These findings suggest that each of these types of carbohydrate can serve as effective sources of carbohydrate to ingest with protein following intense resistance exercise in an attempt to optimize carbohydrate availability as well as post-exercise anabolism.”
Effects of ingesting protein with various forms of carbohydrate following resistance-exercise on substrate availability and markers of anabolism, catabolism, and immunity.
Abstract
BACKGROUND:
Ingestion of carbohydrate (CHO) and protein (PRO) following intense exercise has been reported to increase insulin levels, optimize glycogen resynthesis, enhance PRO synthesis, and lessen the immuno-suppressive effects of intense exercise. Since different forms of CHO have varying glycemic effects, the purpose of this study was to determine whether the type of CHO ingested with PRO following resistance-exercise affects blood glucose availability and insulin levels, markers of anabolism and catabolism, and/or general immune markers.
METHODS:
40 resistance-trained subjects performed a standardized resistance training workout and then ingested in a double blind and randomized manner 40 g of whey PRO with 120 g of sucrose (S), honey powder (H), or maltodextrin (M). A non-supplemented control group (C) was also evaluated. Blood samples were collected prior to and following exercise as well as 30, 60, 90, and 120 min after ingestion of the supplements. Data were analyzed by repeated measures ANOVA or ANCOVA using baseline values as a covariate if necessary.
RESULTS:
Glucose concentration 30 min following ingestion showed the H group (7.12 +/- 0.2 mmol/L) to be greater than S (5.53 +/- 0.6 mmol/L; p < 0.03); M (6.02 +/- 0.8 mmol/L; p < 0.05), and C (5.44 +/- 0.18 mmol/L; p < 0.0002) groups. No significant differences were observed among groups in glucose area under the curve (AUC) values, although the H group showed a trend versus control (p = 0.06). Insulin response for each treatment was significant by time (p < 0.0001), treatment (p < 0.0001) and AUC (p < 0.0001). 30-min peak post-feeding insulin for S (136.2 +/- 15.6 uIU/mL), H (150.1 +/- 25.39 uIU/mL), and M (154.8 +/- 18.9 uIU/mL) were greater than C (8.7 +/- 2.9 uIU/mL) as was AUC with no significant differences observed among types of CHO. No significant group x time effects were observed among groups in testosterone, cortisol, the ratio of testosterone to cortisol, muscle and liver enzymes, or general markers of immunity.
CONCLUSION:
CHO and PRO ingestion following exercise significantly influences glucose and insulin concentrations. Although some trends were observed suggesting that H maintained blood glucose levels to a better degree, no significant differences were observed among types of CHO ingested on insulin levels. These findings suggest that each of these forms of CHO can serve as effective sources of CHO to ingest with PRO in and attempt to promote post-exercise anabolic responses.
PMID: 17997840 [PubMed] PMCID: PMC2206056
Source: http://www.ncbi.nlm.nih.gov/pubmed/17997840
