Notice the difference. Push out your stomach. Point your toes toward your face. Point your toes away from your face. Curl your toes, and simultaneously tighten calves, thighs, and buttocks.
Proper breathing is another antidote to stress and tension.
Shallow breathing contributes to poorly purified or oxygenated blood which then leads to anxiety states, depression, and fatigue. The following breathing exercises will help you to reduce the above. Keep spine straight. Place one hand on your abdomen and one hand on your chest. Inhale deeply through your nose and cause your abdomen to rise and push your hand up.