The Street. No Storage, that’s a plus!
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An elliptical
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ablounge….its small and compact and works amazingly!
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an open road to run on…. its the best burner and free
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dang it i was gonna say treadmill. y did u have 2 steal my answer:(
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eliptical and the stepper. You burn more calories then on a treadmill trust me. It works wonders
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cycle is also good for burn calories
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you mention storage-thats where most machine wind up-thats the only time you will get exercise.
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A small rowing machine
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Elliptical, as more of your body is being worked out, also its low impact.

I just tried a cross between an elliptical and stepper, works awesome.

They sell ellipticals where the legs and entire rear end of the machine fold up.
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Certified Personal Trainer

eliptical.
another is a mini trampoline! it is great!
hope this works
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Interestingly enough a great machine for exercise and burning calories is called Legs.
Hit the pavement and see the results in a month or two
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maby like one of those ab lounges….or a bar with a bunch of handles on it that can be used for pull ups/chin ups push ups, tri-extentions and dips…i forgot what its called though
ladies answer mine plz http://answers.yahoo.com/question/index;_ylt=Ao7JVGijRlm0GIvV6RaL6Jjsy6IX;_ylv=3?qid=20100101153416AA0ef0W
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i think the running ones. Like the treadmill, the stair type one, sorry i don’t really know the official names. But anything will work really, just especially those:)
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your living room floor is good enough for a very intense workout with no equipment needed.
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http://www.madefittv.com/2009/01/tabata-training-method-ep-32-made-fit-tv/

a jump rope
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I agree, your best bet is an elliptical.
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Stationary bike.
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A spin bike is generally a good machine. Easilly stored in a corner and utilzes big muscle groups of the thighs. There are also some fold up rowers that are good. just remember the more muscles and bigger the muscles used the higher the calorie expenditure will be. This is a result of your heart rate increasing to supply the oxygen demand of your muscles, so please consider that calorie expenditure has more to do with intensity of the exercise than the type of machine used. Try to keep your heart rate between 70 - 80% of it maximum to burn calories effecively. To do this follow the steps below.

Step 1 - take your age away from 220

Step 2 - multiply your answer in step 1 by .7 & .8 to get 70-80% of your max heart rate.

Step 3 - periodically check your pulse during your session to make sure it stays within the recommended zone.

Hope this helps.
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My Husband is a full time personal trainer for the last 8years.