Leg and Arm suppression bands
also known as bfr or blood flow restriction bands

Science Behind them 

Blood flow suppression bands can be a great product to incorporate into your training routine and can have results when used correctly. 
However when used incorrectly they can be dangerous and can permanently injure your body. 

* The purpose of the bands is to slow or stop the movement of the blood that is flowing back to your heart. This allows the limbs that are doing the workout to become engorged with blood. 

How Long to have them on???

This is a big question and does not have a specific answer as research shows different  answers. The best way to go about it is to go by what feels right. One should tighten or apply the bands before your first set if you feel any pain or loss of feeling or tingling then you should release them and allow blood to flow again. but if you can do  Three to five sets of each exercise are completed to volitional fatigue. This is done to ensure that there is a high metabolic buildup. The rest periods are 30 seconds to 1 minute in length and occur between every set, with the occlusion still being applied . At the conclusion of the last set, release the straps and blood flow is restored to the muscle

When using Leg Suppression bands.

This specific type of veinous occlusion significantly increases the concentration lactate in your blood, at lower workout intensity or weight. This, in essence, simulates the feeling of a much harder workout in the muscles while also tricking the brain into thinking the body is performing a very difficult workout. As a result, your pituitary gland (a tiny organ found at the base of the brain) releases more growth hormones (reportedly up to 170 percent more) along with hormones that are directly related to muscle hypertrophy (muscle growth) including IGF-1, MTORC1, and myostatin.

Where to put the bands?
Put them as high up on the arms or legs as possible without restricting your movements. 

How Does Occlusion Training Work?

By restricting the blood flow in and out of the working muscles you achieve what is called Cell Swelling, which is directly linked to muscle gain. That swelling, combined with a buildup of metabolites (or Metabolic Stress), has been shown to activate more muscle fibers—even at lower than usual intensities.

The three ways that BFR training is thought to work are:

*The muscle cells become so full of fluid that they must grow (or burst)
*The low oxygen level in a muscle during the accumulation of blood forces your body to recruit the larger fast-twitch fibers, which can stimulate more muscle growth
*When oxygen is low, lactate rapidly accumulates, and many studies show that lactate (also known as lactic acid) can increase protein synthesis

A 2016 Sports Medicine systematic review found that occlusion training increased muscle size and strength in the shoulders, chest, and arms better than conventional training. In fact, the review concluded, “Current evidence suggests that the addition of BFR to dynamic exercise training is effective for augmenting changes in both muscle strength and size.”

In our body, muscles are made of two types of fibers: Type 2 & Type 1. Type 2 fibers are generally known as the fibers that grow easily. The trouble is that Type 2 fibers only really get involved in your resistance training workout when you go to all the way to failure or when you use very heavy weights. This is generally pegged at about 80 percent of your 1RM or 1 rep max (your 1-rep max is the most weight that you can lift once and only once). So, when lighter loads (below 80 percent of your 1RM) are combined with occlusion, the Type 2 fibers are recruited much easier and earlier, allowing you to get bigger, faster and without having to lift as heavy of a weight.

How Tight Is Tight Enough?

The tourniquets should be good and snug, but not so snug that you start to feel pins and needle. If any of your extremities start to go white or blue, you are restricting arterial flow—and that is definitely too tight!

How heavy Is heavy enough?

All the research I have found indicates that there is no benefit to be gained from lifting too heavy with the occlusion bands on. In fact, using a weight that is merely 20 to 40 percent of your 1RM is enough. But beware—even though this sounds easy, you will be suffering by the end. I would suggest starting with four sets of 15 reps with 30 seconds rest between each to maximize muscle growth. You can do this workout two times per week safely with a maximum of three times per week with 48 to 72 hours of recovery between each.

So to sum it up 

Go light and to really focus on pushing the blood into your muscles. 

Don't have them on to long.

If you feel any pain or numbness  RELEASE THE BANDS. 

Leg Suppression bands.

Arm suppression bands

CHECK OUT SOME OF THESE WORKOUTS PEOPLE ARE DOING WITH THEM.