New moms who want to get fit should resume exercise routines slowly, "as soon as it is physically and medically safe" -- and okayed by a doctor, according to guidelines issued in 2002 by the American College of Obstetricians and Gynecologists. How quickly they can safely get started varies; some women can begin exercising within a few days of delivery. Resuming exercise after pregnancy has been linked to a decreased incidence of postpartum depression as long as the activity is "stress relieving and not stress provoking," the report says.

Here are some Washington area options for exercising with baby in tow.

Baby Boot Camp www.babybootcamp.com Program focuses on "building strength, improving posture and increasing core strength and flexibility." Moms, nannies and babies (6 weeks to 2 years) welcome. Daily classes, 60 to 75 minutes. Cost: $12 for a single class to $81 for a nine-class package. In Montgomery County, 301-461-6605.

Stroller Strides www.stollerstrides.com Program for moms and babies (6 weeks and older) includes power walking and body toning exercises. Cost: $3 to $12 a class. Hour-long classes (50 minutes of walking, 10 minutes of stretching and abs exercises) offered several times a week. In Maryland, Virginia and the District. 866-FIT-4MOM.

Many community centers and yoga studios offer classes that lead moms and dads in yoga, incorporating the baby in the poses. Some offer discounted rates when parents enroll in a full session (consisting of several weeks of classes). Sites include:

Shanti Yoga, Bethesda. Weekly mom and baby ($80 for eight-week session) and family ($130) classes. Drop-ins: $12. 301-654-6759, http://schooloflife.org/mothers.

Sun & Moon Yoga Studios, Arlington. Weekly postnatal classes. Cost: $102 to $180 a session. Prorated packages offered. Drop-ins: $18. 703-525-YOGA, www.sunandmoonstudio.com

Budding Yogis, the District. Weekly family and mommy/daddy & baby classes. Cost: $16 a class for registered parents. Drop-ins: $18. 202-686-1104, www.buddingyogis.com.

Willow Street Yoga Center, Silver Spring and Takoma Park. Weekly parent-baby classes. Cost: $104 to $169 a session. Drop-ins: $15. 301-270-8038, www.willowstreetyoga.com

Moore than Yoga, Alexandria/Arlington. Weekly postpartum classes. Cost: $100 for eight-week session. Drop-ins: $16. Babies aged 1 month to 8 months welcome. 703-671-2435, www.moorethanyoga.com

Yoga Tales, Bethesda. "Baby & Me" classes. Babies 4 weeks to active crawling welcome. Cost: $200 for 10 classes. Drop-ins: $22. 301-951-YOGA, www.yogatales.com

The Health Advantage Yoga Center, Herndon. Weekly postpartum classes. Babies 6 weeks to 6 months welcome. Cost: $80 to $130 a session. Drop-ins: $13. 703-435-1571, www.healthadvantageyoga.com

-- January W. Payne

Sources: www.washingtonparent.com, www.babybootcamp.com, www.strollerstrides.com

Baby Boot Camp: Tots come along for the ride.