High intensity interval training is arguably the most effective form of cardio for burning fat and preserving muscle. Yes, H.I.I.T. does both. H.I.I.T. is typically defined as alternating periods of very high intensity exercise (sprinting, cycling, swimming, etc.) with periods of low intensity periods. Despite it being developed long ago by track coaches, it is very useful today. Let’s be honest, cardio can be pretty boring. H.I.I.T. allows people to get more out of cardio sessions and in less time. Not to mention that it can be done anywhere and with no equipment.
There are a constant stream of studies, but the gist is that H.I.I.T. is great for burning fat, especially compared to steady-state cardio. Depending on the research one can burn fat up to 6 times faster using H.I.I.T. and there are even cases of study participants decreasing body fat by 2% in only 2 months. H.I.I.T. burns more calories faster, and the metabolism is boosted for up to 24 hours following a session, for even more calorie burn. H.I.I.T. has also been shown to promote the utilization of fat for energy.
H.I.I.T. promotes muscle growth for the above reason, the body utilizing fat for fuel prevents if from breaking down muscle for fuel. One study found that during a 6-week H.I.I.T. program participants, supplementing with beta-alanine, gained an average of 2 lbs. Of muscle after only 3 weeks, WITH NO WEIGHT TRAINING. H.I.I.T. can increase testosterone production in men as well. Some studies have seen a 100% increase in testosterone levels.
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