Each bean contains 0.8 - 2.5 % caffeine. For your information in an average cup of coffee you have 75mg caffeine. One cup of coffee contains around 25 coffee beans, and you are not getting the full coffee bean in coffee, so the caffeine can add up if you eat a lot.
The reason why temperature effects muscles is because of the numerous atoms in the body that react to temperature. When the air, or body temperature is colder the atoms tend to stay closer together, causing less movement...when it is hot, the atoms (molecules) move around more, causing more range of motion. It also allows blood to flow more easily when it is warm than cold.
Effect of Temperature on Muscle Action. This is an image of me making fists (over 20 seconds) before and after submerging my hand in ice water. This is me soaking my hand in a bowl of ice water for one minute. Here is a table of my results concerning the effects of temperature on muscle action. Effect of Fatigue on Muscle Action. Here is an image of me squeezing a tennis ball. Here is a table of my results concerning the effects of fatigue on muscle action.