Can’t decide between hitting the gym and hitting the club? How about both — thanks to high-heel fitness classes, women (and adventurous men) can go from working out to the bar scene without changing shoes. But high heeled workouts might do more than just make your feet tired — can working out in sky-high stilettos do more harm than good? Read on for the truth on high heels and exercise.

What’s the Deal?

Fitness classes centered on elevated footwear are popping up all over the country with names like Heel Hop, High Heel Workout, Stiletto Strength, and Stiletto Workout. Enthusiasts and instructors claim the workouts tone “feminine curves” and focus on core strength, which helps women feel more stable and confident in their footwear of choice. While each class and trainer has a specific style, most of the workouts focus on controlled movements like lunges, squats, and lifting hand weights, although some also feature cardio dance elements.

All of the workouts sound like they’d work up a sweat, but what’s the rationale for slipping into stilettos before heading to the gym? According to high heel aficionados, the difference is in the elevation. The websites for classes like NYC’s NDG FIT Stiletto Workout claim that working out in fancy footwear engages the core, tones the whole body, and improves overall posture and confidence when wearing high heels. Literally taking fitness levels up a notch sounds tempting, but doctors and podiatrists remain unanimous: They advise lacing up those ho-hum cross-trainers (or even going minimalist) instead and running away far from a high-heel fitness class as possible.

The Answer/Debate

Physicians’ warning against the ills of high heels (and fashionable folks promptly ignoring the advice) is hardly a new phenomenonA history of medical scientists on high heels. Linder, M., Saltzman, C.L. College of Law, University of Iowa. International Journal of Health Services: Planning, Administration, Evaluation, 1998;28(2):201-25. Docs have been advocating sensible footwear since Martha Washington started strutting around Mount Vernon in 4-inch stilettos. Wearing high heels often has been proven to put increased pressure on knee and ankle joints, which can lead to osteoarthritis over timeWalking on high heels changes muscle activity and the dynamics of human walking significantly. Simonsen EB, Svendsen MB, Norreslet A, Baldvinsson HK, Heilskov-Hansen T, Larsen PK, Aljaer T, Henriksen M. Department of Neuroscience and Pharmacology, The Panum Institute, University of Copenhagen, Copenhagen, Denmark. Journal of Applied Biomechanics, 2012 February; 28(1):20-8.Moderate-Heeled Shoes and Knee Joint Torques Relevant to the Development and Progression of Knee Osteoarthritis. Kerrigan, D.C., Johansson, J.L., Bryant M.G., et al. Department of Physical Medicine and Rehabilitation, University of Virginia, Charlottesville, VA. Archives of Physical Medicine and Rehabilitation, 2005 May;86(5):871-5.. Contrary to stiletto fitness instructors’ claims, wearing heels can actually negatively affect posture by tilting the pelvis so the lumbar spine is strainedPostural alignment in barefoot and high-heeled stance. Opila KA, Wagner SS, Schiowitz S, Chen J. Department of Biomechanics, New York College of Osteopathic Medicine, New York Institute of Technology, Old Westbury. Spine. 1998 May; 13(542-7).. Hangin’ out in heels regularly (up to 40 hours per week for two years or more) can also shorten calf muscles and Achilles tendons and lead to hypertension or muscle fatigue in the lower limbsInfluence of high-heeled shoes on venous function in young women. Tedeschi Filho W, Dezzotti NR, Joviliano EE, Moriya T, Piccinato CE. Ribeirao Preto Medical School, Division of Vascular and Endovascular Surgery, University of Sao Paulo, Sao Paulo, Brazil. Journal of Vascular Surgery. 2012 Octover; 56(4):1039-44.Long-term use of high-heeled shoes alters the neuromechanics of human walking. Cronin NJ, Barrett RS, Carty CP. Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Jyvaskyla, Finland. Journal of Applied Physiology. 2012 March; 112(6):1054-8..

If all of those side effects stem from regular everyday wear, how does sweating in stilettos affect the bod? Working out in high heels — from a weights routine to Kelly Ripa’s “High-Heel-a-Thon” fundraiser for the March of Dimes — is dangerous because it’s unstable. A high heel has a smaller point of contact with the floor than a regular shoe, making the possibility of falling (and rolling an ankle or worse) much higher. If just one misstep while wearing high heels can lead to a sprain or broken joint, why tempt fate by doing squats and dance routines in unsupportive footwear? Regardless of the real or invented fitness benefits of exercising in heels, it’s definitely better to stick to neutral footwear in the gym. To get a more intense core or booty workout, up the ante on reps or introduce some heavier weights instead. For ideas on less controversial fitness gear, check out Greatist’s ultimate guide to choosing the right workout footwear.

Would you ever sign up for a high-heel workout? Tell us your thoughts in the comments below or tweet the author @SophBreene.