Yes there are, these benefits include less cravings for sweets, increased energy levels, improved dental hygiene and slightly less commonly, fewer headaches.
No (unfortunately), bread is not a low carb food. For more information about low carbohydrate foods, and what is and what is not a low carb food, see the page link, further down this page, listed...
A hot tub should help your muscles and body relax. For the muscles this will help with strain and overexertion. For the body this can help with high blood pressure and general well being.
Yes, low carb bread can be made in bread machines. There are a plethora of low carbohydrate bread recipes online as well as many low carb diet books which include recipes.