Weighing in on everything from “fat genes” to bulky thighs, our experts share how you can easily make the most of what nature gave you.

  1. You STILL can’t touch your toes Everyone has at least one yogi pal who can do ungodly things with her body while you struggle to so much as touch your toes. You’re better off comparing yourself to your sister or your mom than your contortionist friend, though. “In general, genetics does play a role in flexibility,” says C. David Geier, Jr., MD, director of sports medicine at the Medical University of South Carolina. “Some people naturally have larger ranges of motion with their knees, shoulders, back, and other joints and areas.” How to beat it: Most people can improve their overall flexibility, but, like multiple forms of fitness, it requires routine work, says Dr. Geier. Incorporate daily stretching programs for different body parts and muscle groups into your regular exercise routines.
  2. You have the “fat gene” If your parents are obese, you run a higher risk of following in their footsteps. Studies on twins show high BMI correlations in adulthood—even in those who have been raised apart from one another, says Brad Schoenfeld, MS, CSCS, author of Sculpting Her Body Perfect. “This indicates a genetic predisposition to obesity and ultimately makes it more difficult for some people to lose weight compared to others.” How to beat it: Exercise can keep those genes under your control and reduce your genetic predisposition by 40 percent. A 2008 study published in the Archives of Internal Medicine showed that among Amish people with the FTO gene, a gene associated with obesity and a high BMI, physical activity prevented the weight gain typically seen in people with the gene. The American College of Sports Medicine recommends 30 minutes of activity on most days of the week. MORE:7 Causes of Weight Gain You Can’t Control
  3. You have two left feet If you’ve tried to no avail to become a better dancer (or to at least avoid embarrassing yourself at weddings), you can take comfort in the fact that it’s not your fault. “Everyone’s genetic makeup contributes to their ability to perform both physical and mental tasks,” says Daniel Kantor, MD, neurologist and president of the Florida Society of Neurology. “Coordination is mediated by the cerebellum in the back of the brain, the visual system and the sensory system.” And as with any sport, dance is easy for those who are naturally gifted at them. How to beat it: Just as athletes progress when they perform grueling practices and drills, the average woman can improve her coordination through balance training, says Dr. Kantor. “Even technologically savvy apps such as the Wii system can help.” Start with simple balance exercises, such as standing on one leg while performing biceps curls. (Work your core and improve your balance with these 6 Surprising Moves for Flatter Abs.)
  4. Weights make you bulk up “Studies with twins show that up to 90 percent of your baseline muscle strength is hereditary,” says Schoenfeld. This is believed to be at least partly due to variations in fiber type. If you have more slow-twitch (type I) fibers, you’re predisposed to be able to perform endurance-related activities, but you would have a harder time increasing your muscle mass. Conversely, a person with more fast-twitch fibers (type II) might bulk up easily but have a tougher time with endurance, says Schoenfeld.   How to beat it: If you aren’t building muscle even from a regular weight-lifting program, you may have more type I fibers. (True testing requires a muscle biopsy.) If so, try using higher reps (15 or more) and less weight. If you tend to develop bulky muscle quickly, more weight and fewer reps are your best bet.
  5. You have weak bones If osteoporosis runs in your family you may be at a higher risk of developing the disease, too. Your bone mineral density (BMD) is between 50 to 90 percent determined by heredity, according to a study from the journal Endocrine. “Lineage might suggest a tendency toward it but other variables must also be considered, such as calcium and vitamin D intake,” says Irv Rubenstein, PhD, exercise physiologist and founder of STEPS, a fitness facility in Nashville, TN. How to beat it: To stay ahead of the curve, after age 30 when bones and joints are still healthy, get involved in sports activities on a daily basis, says Dr. Rubenstein. Try brisk walking, jogging, and even light plyometrics (explosive movements such as squat jumps). [To get started on a fat-burning walk or run program, check out our free downloadable training plans.]  Plus, focus on resistance training with an emphasis on your lower body. For example: squats, leg presses, lunges and one-legged squats. 
  6. You tire out quickly If you and your friend do the same cardio class but you’re exhausted 10 minutes in and she’s barely working up a sweat, it might not be your fault. A gene may determine which one of you reaps the greater benefits, according to a 2011 study published in the Journal of Applied Physiology. Researchers from the Pennington Biomedical Research Center in Baton Rouge, La., looked at the genomes (a full set of chromosomes) of 473 healthy volunteers. Study participants who possessed 19 or more of tiny DNA segments called single-nucleotide polymorphisms (SNPs), improved their cardiovascular fitness three times as much as those with nine or fewer.  How to beat it: You may never be the next Usain Bolt, but you can improve your cardiovascular fitness by doing interval training with a focus on anaerobic capacity, says Dr. Rubenstein. A simple interval routine you can try: Warm up for 3 to 5 minutes and then alternate 60 seconds of walking with 30 seconds of running. Adapt the interval times to suit your fitness level. For more ideas onhow to torch more calories in less time, check out these easy workouts, too.