[WaltPurvis]

Agreed with all that, but I'd add that it's not truly necessary to do cardio "for at least 30 minutes." High intensity interval training (you can google for HIIT if you're interested) is proven to be just as effective, if not more, than longer steadier cardio workouts.

Personally I alternate between both.

[tom_b]

Interesting research results contradict HIIT as a pure general guideline for everyone (I think alternating between both is an excellent approach though).

"Given that ∼20% of subjects fail to improve aerobic capacity with intense endurance training, while ∼30% do not enhance their insulin sensitivity (12), it is clear that we must develop genotype-tailored lifestyle interventions."[1]

[1] Using molecular classification to predict gains in maximal aerobic capacity following endurance exercise training in humans

James A. Timmons, Steen Knudsen, Tuomo Rankinen, Lauren G. Koch, Mark Sarzynski, Thomas Jensen, Pernille Keller, Camilla Scheele, Niels B. J. Vollaard, Søren Nielsen, Thorbjörn Åkerström, Ormond A. MacDougald, Eva Jansson, Paul L. Greenhaff, Mark A. Tarnopolsky, Luc J. C. van Loon, Bente K. Pedersen, Carl Johan Sundberg, Claes Wahlestedt, Steven L. Britton, Claude Bouchard Journal of Applied Physiology Published 1 June 2010 Vol. 108 no. 6, 1487-1496 DOI: 10.1152/japplphysiol.01295.2009