"My weight loss has stalled, should I do more 'cardio' or strength training?"
Dr. Oz responds by saying you need to raise your metabolism to help burn more fat and Calories. So far I agree. Then he shows either his ignorance, or just blatant pandering to a predominant female audience. He says NOT to do heavy weight lifting, but to raise your metabolism by performing yoga and Pilates!
What! I can not believe what horrible exercise training information the doctor is spewing out to his viewers. While yoga and Pilates do offer physical benefits, their ability to raise metabolism, burn body fat doesn't hold a candle to heavy/high-intensity strength training and or interval training. I have personally used strength training as my main tool to help clients raise their metabolism and lose body fat. I have been able to help many women significantly change their body composition.
But, I do not want to feel like I am just projecting my biases either, so I did a Pub-Med search to review some original research on the topic. It is pretty well established that strength training is very good at improving body composition even without changes in nutrition and over relatively short (10 weeks) period of time. In a recent study by Ferreira, et. al. (2010), women aged 33-45, who performed a stength training circuit three days per week, lost 9 pounds of fat and gained six pounds of lean mass (which they had most likely lost over the last couple decades from being inactive).
However, Yoga (which one study showed energy expenditure equivalent to walking at 3.5 mph) and pilates are not as effective. A 2004 Observational study by Segal, et. al. showed no change in body composition after two, four, or even six months of mat pilates classes. This was a common outcome with these studies on yoga and pilates. I did come across one study where FIVE hours of mat pilates per week resulted in a small improvement in body fat in teenage girls.
Now, I have nothing against yoga or pilates. They each offer a method of improving aspects of fitness. I even use some yoga exercises to enhance joint mobility and some pilates to enhance torso stability. The issue is that neither yoga or pilates are as metabolically demanding as heavy/high-intensity strength or interval training to help you shed body fat.
So the answer to the women's question should have been: three days a week do (relatively) heavy/ high-intensity strength training and two days of some sort of high-intensity interval training. By far, that would be more effective than yoga or pilates, even added to what most people consider 'cardio' (low-mod intensity, steady-state exercise).
However, Dr. Oz was just pandering to his predominantly female audience who are heavily influenced by the media and 'celebrity trainers'. The irrational fear of lifting heavy weights and getting bulky is absurd. Especially when there is overwhelming, scientific research to support how effective and efficient heavy/high-intensity strength training really is for helping you lose body fat.