improving endurance and stamina

Question
hi ryan,

i'm anand, 25, m, from india;
my height 175cms weight 65kgs;

i like to share my feelings on my fitness;
before 3 or 4 years i feel very energetic and active,in the way without even training or effort in my college days i take part in 100m 400m 800m long jump got in first 3 places.

but in last 4 or 5 my physical activity reduced. i grown very lazy. now even claiming staircase, somewhat make me to sweat more and jogging 1 km makes me feel exhausted. amazingly i'm not over weight.

i read some articles by anthony robbins(author, awaken the giant within), said when we do aerobics with maximum heart rate we feel exhausted bcoz we use glucose as primary fuel to burn instead of excess body fat, thus we associate lots of pain in doing exercises, by pushing the body like this.
he also insist to invest in good heart rate monitor, for aerobics activities.

ryan, you are an expert, you must guide me in
enjoying my aerobics exercises especially jogging now.
which heart rate monitor is good for me.

note:- i like to run long distance. how can i train my body to run atleast short marathon. i love to be healthy.what are the steps  i need to take.

thanks ryan
i'm waiting for your guidance.


Answer
You don't need a heart monitor, learn to run how you feel and listen to your body. Your body will perform the same taks at different heart levels on different days due to freshness or fatigue. Therefore, if you base everything on heart rate, you may overwork your body on easy days and underwork on hard days. Run for time not distance.

Ryan