First I will finish up with milk and answer a couple of questions. Then I will tackle Baking Soda as a performance enhancing drug.
I had a couple questions about cheese and yogurt. No, they do NOT elicit the same insulin response as milk. Ice cream has a substantial insulin response, but it is what you would expect from the amount of sugar available in ice cream. This is another reason that I don't drink milk.
I talked last time about how it wasn't the fat in milk that caused the insulin spike, and it wasn't the carbohydrates either. That leaves the protein as the culprit. Yogurt and cheese have the exact same protein composition as milk, but they don't produce an insulin spike. That's odd. If you ask a nutrition professor about the insulin spike in milk they will tell you that certain amino acids are able to cause an increase in insulin (that's true). Then why does milk increase insulin levels, but not cheese and yogurt? Nobody knows.
It could very well be that it is a combination of fats and protein that some how change things. That is a reasonable explanation. Another explanation (which goes against a lot of "established" science) is that the intact proteins are entering our bodies and having a hormonal influence on our organs.
Most people have heard that mothers should breast feed their babies because it boosts their immune system. That is because breast milk has protease inhibitors (proteins that prevent the baby's gut from breaking down molecules that help the baby) so the baby can absorb mom's healthy stuff into their own system.
Mother cows also produce protease inhibitors that inhibit breakdown of molecules when you drink it. Does that mean that when the farmer shoots up the cow with all sorts of hormones and drugs, they get into our bodies? Scary huh. Frankly, it's a long shot. The adult gut should break down all of the proteins before absorption and any scientist will tell you that is what happens. I agree with them that milk probably is broken down before absorption, but really there isn't any specific data on the subject. (To be fair, there is a lot of data to show that proteins are broken down in the gut before absorption in adults, it just didn't happen to use milk proteins).
OK, bicarbonate. Baking soda (bicarbonate) is a viable performance enhancing drug. Your body uses bicarbonate to buffer lactic acid, so the idea is that if you supplement with baking soda your body will have an increased ability to buffer lactic acid. It works for long sprint events. So if you run the 400 or 800 in track or ride the flying kilo on the velodrome, baking soda could improve your performance. It is not effective for longer distances.
Oh, there are a couple of side effects... Well there's just one SUBSTANTIAL side effect. First off, it takes LOTS of bicarbonate to increase performance (several tablespoons at least). If you can get down several large tablespoons of baking soda, that might work for you, but most people buy empty capsules so they can swallow the baking soda and then the capsule dissolves in the stomach. Baking soda is not very well absorbed, so it takes lots. Oh, and because baking soda is not very well absorbed, it causes the diffusion of water into the colon. The major side effect of using baking soda is EXPLOSIVE diarrhea. While you will likely improve your 400 time, I don't know if it will be a lactic acid buffering thing, or a severe urge to get to the bathroom before embarrassing yourself. Try it at your own risk.
Something that really does work for similar events is hyperventilating at the starting line which will increase your ability to buffer lactic acid. The only risk there is passing out before the gun goes off.