Extended periods of sitting at your workstation affect your physical structure, locking your hips, making your shoulders slump, and limiting the flexibility of your spine. Therefore, the following mobility exercises and stretching are essential to increase the blood flow to your muscles and correct your posture. Below you will find a list of 8 exercises that help reduce stiffness acquired during extended periods of sitting at your workstation:
Thoracic Windmills

Lying on your side, bend your knees to a ninety-degree angle. Place your hands before you and let them touch each other. Fix your knees to the ground and make an arc in the air from your head down to your legs with one arm, simultaneously twisting your back upwards until the opposite shoulder touches the ground.
90/90 Hip Switch

Sit on the ground and bend your right leg at 90 degrees in front of you, your left leg bent in the same manner but to the side. Keep your posture and feet on the floor, then cross the angle of your knees from one side to another so that your right leg ends up in front of you.
This exercise helps with both internal and external hip rotations, which become frozen with extended periods of sitting.
Prone Y-T-W Raises

Lying flat on the floor facing down, lift your body a little off the floor using your arms to form a Y position. In this regard, you are supposed to stretch your hands from the Y formation to the T formation, raising your chest again with your arms spread out. Lastly, move your elbows down to the W formation and raise your chest. In this way, you will build the muscles of your back and improve your posture.
Doorway Chest Stretch

Facing a doorway, place your forearms in the doorway, making an angle of 90 degrees parallel to your shoulders. Step through the doorway with one foot while you stretch your chest and anterior shoulder muscles comfortably.
Shoulder CARs (Scapular Car-Washes)

Stand with feet shoulder-width apart while one hand extends downward fully towards the floor at your side and the other extends out fully in front of you. Perform the biggest circles with the extended arm. The arm will move in an upward direction towards the ceiling, rotating the palm away from you once it has reached the highest point.
Figure Four Seated Stretch

Start by sitting on the office chair, keeping your right ankle on your left knee. Curl your right foot inward so that you can protect your knee joints. Make sure that you keep your body posture right, then bend forward from your waist till your chest touches your knees.
Glute Bridges

Sit on the floor and bend your knees. Now place your heels close to the floor and press down on your heels, lifting your hips towards the ceiling to form a straight line from your hips to your knees. Your glutes become inactive while you sit for hours, and this exercise works well on them.
Ankle Rolls and Foot Compressions

Raise one of your legs and rotate it in ten rolls in both clockwise and anticlockwise directions. Point your toes downward and raise them up high. It will help you to release any excess fluid in your legs due to prolonged sitting and ease any pressure build-up.