YELLOW

Yellow resistance bands are great for beginners. They offer light resistance and are very stretchy. It means that it takes little effort to pull against them. Usually, light resistance bands are used to do some exercises which use joints such as shoulders and shins and you don’t need much resistance to break through. 

RED

Green resistance bands offer medium resistance and have more tension than yellow resistance bands, If you’re looking for a step up from the beginner, green resistance bands are your next step. Green resistance bands are used to do some exercises that need slightly more tension. You can work your muscle like biceps and triceps

GREEN

Red resistance bands have a higher level of tension than green and yellow. After you’ve been building muscle strength for a few days and are ready to try more resistance challenging, go with a red resistance band. Red resistance bands are used for muscle work such as legs, back, and chest.

BLUE

Blue resistance bands are much stiff and are heavy resistance. They’re harder to pull and require quite a bit of strength compared to their less intense counterparts. Blue bands are for someone who is very strong, or for larger muscle groups, such as the legs, chest, and back. These are also the bands to use when working out with someone else and when two people pull against a band.

BLACK

Black resistance bands are the heaviest resistance to pull and stretch but also makes that workout quite a bit more challenging than one done with a green or red band. Black bands are used for the large muscle groups, such as the legs, or when working with someone else. Someone may think it's cool to use black resistance bands but it should be used in the right way. If you don't have a strong muscle, it's not appropriate for you to use the black bands.