After the first trimester, it is recommended that pregnant women don't spend an extended amount of time on their back due to the pressure that the uterus can put on the Inferior Vena Cava. (The Inferior Vena Cava is the big vein in your belly that brings blood back to the heart)
Instead of giving up on doing all exercises that require you to be on your back, there are some modifications that can be used in order to reap the benefits of exercising in supine.
Place a wedge behind your head and shoulders so that you are in a reclined position where your heart is above your navel
Prop yourself up on your arms so that your head and shoulders are off the floor and your heart is above your navel.
Exercises in modified supine target your core (abdominals, pelvis, obliques), thighs, legs, buttocks.
Heel Slides:
Begin in a supine position with your knees bent and feet flat on the floor, shoulder width apart.
Supine: laying on your back or with a wedge/arms behind your back so that your heart is above your navel if beyond 1st trimester
Slide your foot forward along the floor and hold it there for 5 seconds, then slide your foot back up to start position. 10-15 reps on each side
Make sure you are engaging your abdomen: bring your bellybutton in toward your spine and up toward your nose instead of pushing your bellybutton out
Remember to breathe in and breathe out when you are straining
To make this exercise harder point your toes up toward your nose to activate your upper leg muscles
To make this exercise harder try not to touch the floor while sliding your foot out and in, keep it above the floor an inch
This exercise engages your core, your pelvis, your quads and your calves
Stationary Leg Lift:
Begin in a supine position with your knees bent and feet flat on the floor, shoulder width apart.
Supine: laying on your back or with a wedge/arms behind your back so that your heart is above your navel if beyond 1st trimester
Lift up one leg (no higher than the knee of your other leg) so that your leg is straight, knee isn’t bent, toes facing up toward your nose, and make sure you feel your quads activate. Hold the lift for 10-15 seconds and then switch legs (10 reps each leg)
Make sure you are engaging your abdomen: bring your bellybutton in toward your spine and up toward your nose instead of pushing your bellybutton out
Remember to breathe in, and breathe out when you are straining
You can vary the position of the leg that you are lifting to activate different parts of your thigh muscles; you can have it very close to the ground, midway from the ground, or higher up where your knee meets the bent knee of your other leg. You should feel parts of your thighs are working as you vary the position.
This exercise engages your core, your pelvis, and your quads
Dynamic Leg Lift:
Begin in a supine position with your knees bent and feet flat on the floor, shoulder width apart.
Supine: laying on your back or with a wedge/arms behind your back so that your heart is above your navel if beyond 1st trimester
Lift up one leg (no higher than the knee of your other leg) so that your leg is straight, knee isn’t bent, toes facing up toward your nose, and make sure you feel your quads activate (2 sec) and bring the leg down slowly to almost touch the floor (2 sec) bring the leg back up and repeat (15 reps each leg)
Make sure you are engaging your abdomen: bring your bellybutton in toward your spine and up toward your nose instead of pushing your bellybutton out
Remember to breathe in, and breathe out when you are straining
You can vary the position of the leg that you are lifting to activate different parts of your thigh muscles; you can have it very close to the ground, midway from the ground, or higher up where your knee meets the bent knee of your other leg. You should feel parts of your thighs are working as you vary the position.
This exercise engages your core, your pelvis, and your quads
Bicycle in Supine:
Begin in a supine position with your knees bent and feet flat on the floor, shoulder width apart.
Supine: laying on your back or with a wedge/arms behind your back so that your heart is above your navel if beyond 1st trimester
Make sure you are engaging your abdominal muscles by bringing your bellybutton in toward your spine and up toward your nose to help stabilize your spine
Lift feet off the ground with your thighs vertical to the ground, and knees are bent at a 90 degree angle
Remember to breathe in, and breathe out when you begin the movement and are straining
Bring your right knee in toward your chest while straightening the left knee
Hold the position for 3 seconds and then switch to bending the left knee and straightening the right knee; like riding a bicycle. (10 – 15 reps each leg)
Perform movements slowly and controlled, make sure the core muscles are always engaged to avoid increasing pressure inside the abdomen
Make sure you are taking deep breaths each repetition
This exercise engages your core, your pelvis, and your quads