But take heart: Even high-profile, time-crunched women have found ways to outwit the obstacles and stick with the program.
For Michelle Akers, member of the 1999 U.S. Womens World Cup championship soccer team, injuries through the years have prompted her to get creative in her regimen. She takes time to let her body heal when necessary, but stresses that there's always something you can do to keep active.
Even while sidelined, she maintains fitness on a stationary bike, in the pool, or with weights. When she's training hard, she gives her body and mind needed rest.
I take a full day off from soccer each week," she says. "Instead, I walk or take a slow, relaxing jog, get a massage, and stretch.
For Akers, staying motivated through setbacks is a matter of choosing activities she loves. The champion athlete loves to mountain-climb, hike, water ski, snow ski, ride horses, and swim.
It's important to look forward to whatever activity you participate in, she explains. It can't be something you dread, or you won't stick with it.
Model and new mom Cindy Crawford knows something about having her schedule upended.
Since having my son, I find I have a lot less time to work out, and it's nearly impossible to do it at a scheduled time, she says.
Crawfords plan to return to work within months made getting fit a professional necessity. With little time during the countdown to cameras, Crawford says, I learned to squeeze it in whenever I had a few minutes.
Besides walking at an incline on her treadmill at home, Crawford developed exercise routines to fit whatever blocks of time she had.
There's a 10-minute one, a 20-minute one, and a 35-minute one. I do them when I can. And she has continued to walk outside, a habit she developed while pregnant. My prenatal yoga teacher encouraged us to walk up to five miles a day. I only made it that far once, but I did walk two to three miles a couple times a week. And now? I do those same walks with my little guy in a sling.
Covering NFL, NBA, and WNBA games, NBC sportscaster Hannah Storm is a woman in the spotlight. Between breaking new ground for women in the still-imbalanced world of professional sports and raising two young daughters with her sportscaster husband, Storm works to make fitness a priority.