Designing a fitness program for your prenatal and postnatal clients employs the same components of intensity, duration, frequency, and mode used in the development of an exercise program for any population. The design of a fitness program for prenatal and postnatal clients is similar, but there are differences in contraindications, warning signs and symptoms as well as the level of progression, supervision, and monitoring needed. This section will provide you with the guidelines for developing, monitoring and modifying exercise for pregnant and postpartum women. The goal of exercise for both groups is maintaining or improving fitness, strength, and flexibility through a safe and comfortable fitness program. Keep in mind that each client's needs will be different and your goal is to create and modify her program in a way that enables her to continue to exercise without discomfort or injury.
Prenatal Exercise Prescription
The use of training heart rate to measure intensity during exercise has been determined to be a poor indicator of maternal exertion level. During early pregnancy, vessel dilation (a response to hormones being produced which relax blood vessels) and the resulting vascular underfilling will cause a woman's heart to beat more rapidly to make up for the drop in volume. If she exercises at her usual pre-pregnancy level, her heart rate response will be much higher than normal because of her body's attempt to pump blood out into her system.
As pregnancy progresses, blood volume increases to correct the changes in circulatory volume causing your cardiac output to rise. The amount of blood pumped into the system is increased, so the heart doesn't need to pump as rapidly to meet exercise needs. By late pregnancy, the combined effect of exercise and cardiac output may make it difficult for a pregnant woman to get her heart rate into a training range, even though she may feel that she's working at a somewhat hard level.
Because of the pregnancy-induced changes affecting exercise heart rate response, the most accurate and safe way to gauge exercise intensity is by using the Borg Rating of Perceived Exertion chart (RPE). Pregnant women should exercise at a level that feels moderate to somewhat hard, which corresponds to 12-14 on the 20 point RPE scale, or 4-5 on the newer 10 point scale. Women who haven't exercised before their pregnancy may have a difficult time determining their body's physical signals, so it's helpful to coach them on how to determine their intensity using the RPE scale through several exercise bouts until they feel confident.
The talk test is a practical method that women can use to help monitor their exercise intensity. The key is that they should be able to carry on a conversation with another person during exercise without having to gasp for breath. If this is not possible they should reduce the intensity of their exercise. The talk test is a useful tool for instructors to use in monitoring a client's intensity by providing tangible feedback on her exertion level.
The duration of exercise should be modified to enable the client to achieve a moderate to somewhat hard level of intensity without discomfort or undue fatigue. Some types of exercise, such as non-weight bearing activities like swimming, may require a longer duration in order to achieve a training level. To derive optimal benefits pregnant women need to exercise for at least 20 minutes and may increase the duration as long as her pregnancy is progressing normally and she feels good.
Some women find that they are able to tolerate a longer duration, lower intensity exercise (12 versus 14 on the RPE scale) bout better than higher intensity shorter bout as their pregnancy progresses. Each client must be frequently monitored, and her exercise load should be reduced or discontinued if she experiences any problems or discomfort.
Choosing the type of exercise that is best tolerated during pregnancy depends on the following points:
- What activities does the client enjoy or is skilled at doing?
- Does the activity post any risk to her or her fetus?
- Is she able to do the activity without being compromised by her balance and center of gravity change?
- Can the activity be easily modified as her pregnancy progresses?
- Does common sense tell you that this is a safe activity to continue during pregnancy?
Some researchers have found that greater benefits are attained by including sustained, weight-bearing exercise activities such as walking and jogging in a prenatal fitness program. However, some women may not tolerate weight-bearing exercise during pregnancy and are more comfortable with non-weight bearing activities such as swimming and biking.
Below is the list of absolute and relative contraindicated exercise for pregnant women. Both scuba diving and water-skiing are activities that should be avoided by all pregnant women. The safety of the relative risk activities depends on a woman's skill and her health and fitness level. She should consult with her healthcare provider before attempting any activities that create concern. It is always a good idea to assess the risk/benefit ratio and use common sense whenever there is a question about the safety of any activity during pregnancy.
- Scuba Diving
- Downhill skiing and high altitude sports
- Cross country skiing
- Horseback riding
- Hot tubs and saunas
The number of days each week that a pregnant woman can safely exercise depends upon several factors:
- Her level of fitness
- How her pregnancy is progressing
- The type of activity and intensity
Some women find that they can comfortably exercise up to six days a week as long as they modify their intensity, duration and type of activity as needed to maintain well-being. Three days a week is the minimum needed to achieve benefits and gain improvements in fitness. Reduce exercise frequency if a client shows signs of overtraining and allow for more rest days between exercise sessions.
About the Author: Catherine Cram, MS
Catherine Cram, MS, is the owner of Comprehensive Fitness Consulting, a company that provides pre- and postnatal fitness certifications and information to hospitals, health & wellness organizations, and the military. Catherine earned her Masters Degree in exercise physiology from San Diego State University. She speaks regularly at health and medical conferences and has been featured in articles on maternal fitness in many publications including The American Journal of Medicine & Sports, Women's Health and Fitness, Pregnancy, and Parenting.
She is the author of Fit Pregnancy for Dummies, published by Wiley Publishing in July 2004, and contributing author of Womens Health Care in Physical Therapy: Principles and Practices for Rehabilitation Specialists (Lippincott Williams & Wilkins 2008). She is a maternal exercise consultant on the websites Babyfit.com and Pregnancytoday.com.
Catherine Cram is the instructor for our Seminar-on-Demand Prenatal and Postpartum Fitness Guidelines which can be purchased through our course catalog.