I’ll start with the last question first.
If you’re round-shouldered (kyphosis is the medical term), basically you have had bad posture and been standing/sitting with your shoulders hunched that your pectoral muscles become contracted, thus perpetuating the condition, and making it difficult to assume proper posture without intense concentration. Even with making the effort, the shoulders are pulled forward somewhat. Massage can help relax and lengthen muscles, so if you massage the pecs, they can elongate somewhat, making it easier for the trapezius and rhomboids to do their job, part of which is to keep those shoulders back. One massage obviously isn’t going to fix this, and there should be some exercises done at home to stretch the pectorals. But the general rule is, if there’s pain/problems with a muscle, you should work its antagonist as well as the affected muscle.
Middle question- a lot of the problem is we simply don’t drink enough water. We drink tea, we drink coffee, soda, etc., which really don’t do a lot of good as far as getting those metabolic wastes out of the body tissues, so they just kind of hang out there and can cause problems. Massage increases blood flow to an area. Increased blood flow means that more oxygen, nutrients, etc. are brought into the area, and any excess metabolic wastes are carried out. Of course, if you don’t drink enough water (not coffee, not soda, but water), then the body can’t properly flush itself out, and everything can settle back into the tissues again.
Tummy massaged- again, blood flow to the area is increased, and good blood flow is important to the proper functioning of any body part. Also, massage can increase peristalsis, which helps keep things moving along through the digestive tract. Also, if a person is a bit constipated, just the physical, mechanical pressure can help get things moving again. Squeeze a tube of toothpaste and you’ll see what I mean. One of my instructors advises against doing abdominal massage on elderly clients because they often don’t have good control of their bodily functions, and it does occasionally happen that things move along and out onto the table. I’d hate to be working for the linen service on the day that happens. On a client who is suffering diarrhea, it can be helpful to massage the abdomen in a counterclockwise direction (opposite direction of the movement of the digestive tract). In all other circumstances, clockwise is the rule. If the client has certain intestinal disorders (irritible bowel syndrome is one example) the abdomen should not be massaged.
OK, measurable effects- muscle relaxation, increased circulation, increased muscle tone, increased skin elasticity and improved skin tone, relief of pain, reduced breathing and heart rate, decreased blood pressure, reduction of edema, increased/improved immune function, reduction of depression and anxiety… that’s all I can think of without actually consulting my textbook.
I’m not really sure how much research has been done on reflexology, it seems the evidence of its effectiveness is largely anecdotal, but I will tell you this. In our first reflexology lesson, I was being worked on by a girl who just doesn’t like feet. In particular, she was working the area that corresponds to the spine in a half-assed way. The next day, my back, which I have chronic problems with anyway, was so stiff I was almost immobilized. After some stretching, I gave that area of the foot a good working on and felt quite a bit better. The day before yesterday, my partner overworked the part of the foot that corresponds to the chest, and late that afternoon, I had a really vicious coughing fit. Snarked up a lot of unpleasantness and felt better afterward, but while I was hacking, it wasn’t fun.