How to Modify Your Workouts During Pregnancy

Exercise during pregnancy offers numerous benefits for both mother and baby, from improved mood and energy to better sleep and reduced discomfort. As your body changes to accommodate your growing baby, adapting your fitness routine becomes essential for maintaining strength and wellness while ensuring safety throughout each trimester.

Key Highlights

Here’s what you need to know about exercising safely during pregnancy:

• The American College of Obstetricians and Gynecologists recommends 150 minutes of moderate-intensity activity per week
• Use the “talk test” to monitor exercise intensity instead of heart rate
• After 16 weeks, avoid exercises that require lying flat on your back
• Low-impact activities like swimming, walking, and modified strength training remain safe options throughout pregnancy
• Always consult with your healthcare provider before starting or continuing any exercise program

Understanding Changes: First Trimester Foundations

During the early weeks of pregnancy, many women can continue their pre-pregnancy fitness routines with minimal adjustments if they were already active. The first trimester is an ideal time to establish safe exercise habits that can be modified as pregnancy progresses. While hormone fluctuations may cause fatigue and nausea, gentle movement can actually help alleviate these symptoms for many women.

Focus on maintaining, not increasing, your fitness level during this time. Stay well-hydrated and avoid overheating during workouts, as elevated core temperature can potentially affect fetal development. If you experience persistent nausea, try shorter, more frequent exercise sessions and consider working out during times of day when you feel your best. Many women find that morning sickness improves during the second trimester, allowing for more consistent activity.

Understanding Changes: Safety Monitoring Techniques

Rather than focusing on heart rate zones, which are no longer the recommended method for monitoring exercise intensity during pregnancy, use the “talk test” to gauge your exertion level. You should be able to carry on a conversation while exercising—if you’re too breathless to speak, it’s time to dial back the intensity. This self-monitoring approach is more practical and reliable than heart rate monitoring during pregnancy.

The Rating of Perceived Exertion (RPE) scale is another helpful tool. On a scale of 1-10, aim to keep your exertion between 3-5 (moderate) during most workouts. Pay attention to your body’s signals and be prepared to adjust your expectations as pregnancy progresses. According to the American College of Obstetricians and Gynecologists, the goal isn’t performance improvement but rather maintaining fitness while supporting your changing body.

Your Body & Baby: Second Trimester Modifications

As you enter your second trimester, your growing uterus begins to shift your center of gravity, requiring more significant workout modifications. After 16 weeks, avoid exercises that involve lying flat on your back for extended periods, as this position can compress the vena cava (a major blood vessel), potentially reducing blood flow to your baby. Instead, use inclined positions with pillows or specialized equipment for exercises traditionally done on your back.

During this period, many women experience relief from first-trimester symptoms while enjoying increased energy levels. This makes the second trimester an excellent time to establish consistent exercise habits. However, be aware that pregnancy headaches may occur during the second trimester for some women. If you experience headaches during or after exercise, ensure proper hydration and consider maintaining optimal hydration throughout your pregnancy to help reduce their frequency.

Your Body & Baby: Adapting Core Work

Traditional core exercises like crunches and full planks become increasingly inappropriate as pregnancy progresses. By mid-pregnancy, the growing rectus abdominis muscles may separate (diastasis recti), requiring modified approaches to core strengthening. Replace conventional ab exercises with pregnancy-specific movements that support your changing body without creating excess intra-abdominal pressure.

Focus on functional core work that engages the deeper transverse abdominis muscles, which help support your posture and back. Exercises like standing pelvic tilts, seated ball rotations, and modified side planks can maintain core strength without putting pressure on your abdomen. The American Pregnancy Association emphasizes that proper core strength during pregnancy can help prevent back pain and improve posture as your center of gravity shifts. Remember that maintaining functional strength, not achieving aesthetic goals, should be your priority during this special time.

Healthy Living Tips: Recommended Activities

Several exercise modalities remain safe and beneficial throughout all pregnancy stages when appropriately modified. Swimming and water aerobics are excellent options as they provide cardiovascular benefits while supporting your weight and reducing joint strain. The buoyancy of water can be particularly welcome during the 2nd month of pregnancy and beyond when balance changes begin to occur.

Walking remains one of the most accessible and effective forms of pregnancy exercise, requiring minimal equipment while offering significant cardiovascular benefits. Stationary cycling provides another low-impact option that eliminates fall risks while allowing you to adjust resistance and positioning as your pregnancy advances. Prenatal yoga and Pilates classes specifically designed for expectant mothers can improve flexibility, strengthen core muscles, and teach breathing techniques that may be helpful during labor.

Healthy Living Tips: Knowing When to Stop

Understanding warning signs that indicate when to stop exercising is crucial for protecting both you and your baby. If you experience any vaginal bleeding, fluid leakage, dizziness, chest pain, calf pain with swelling, or decreased fetal movement, stop exercising immediately and contact your healthcare provider. Regular contractions or severe headaches that persist after rest and hydration also warrant medical attention.

Stay vigilant about your body’s signals throughout your pregnancy journey. As delivery approaches, you may need to reduce exercise intensity and duration based on how you feel. The Society for Maternal-Fetal Medicine notes that while exercise is beneficial, listening to your body becomes increasingly important in later pregnancy. Remember that pregnancy is temporary, and maintaining some activity, even if modified, is more beneficial than abandoning exercise completely.

Continuing Your Fitness Journey

Modifying your workouts during pregnancy doesn’t mean abandoning your fitness goals—it means adapting them to support your changing body and growing baby. By understanding proper modifications for each trimester and recognizing your body’s signals, you can maintain an active lifestyle that contributes to a healthy pregnancy experience. Remember that every pregnancy is unique, and what works for one woman may not be appropriate for another, so always consult with your healthcare provider about your specific situation.

Sources

American College of Obstetricians and Gynecologists: Exercise During Pregnancy
American Pregnancy Association: Exercise During Pregnancy
Mayo Clinic: Pregnancy and Exercise
Society for Maternal-Fetal Medicine: Exercise During Pregnancy
American College of Sports Medicine: Exercise During Pregnancy