trainig heart-rate zone

Please,tell me which is the best heart-rate zone for training in percentage? i spend most time in 80-90% of mhr when i am on hilly roads(gradient of descent 10% and less).
can i improve my shape and endurance in this zone,or i should stick in 70-80% of my mhr.
i spend a lot of time above 80% of mhr on a flat roads, too.i started to ride 2weeks ago, and have had 8 trinings since then.
how many training days are needed for some visible improvment(monitoring heart work and speed).
my cadence is about 100 (less or more for a few rpm),and my average speed is about 19ml/h.today i had hilly part about 3 miles with a gradient of descent 8 %,and have had average speed 13.15 ml/h.can u tell me is it to bad,or what.(almost all the way i was at 90-95% of my mhr)

Jovana - that is a very big question. The answer depends on a lot of factors. Can you tell us how old you are and what are your goals?

Do you want to race and if so would you race long distance?

How long have you been riding?

Most athletes will train at lower heart rates (60 to 70% of mhr) in the non-racing season. This allows for development of the aerobic system while still working at an intensity that allows for easy recovery. As you approach racing season, the intensity of your rides should increase. So it really depends on where you are in your training and where are you going with it.

I use the "Triathletes Training Bible" by Joe Friel to guide my training. It's a very good resource and I believe he has a similar book for cyclists.

This may be a good place to start looking around:

http://www2.trainingbible.com/

If you give us some more details, we might be able to help here on TE.

i am 23,and i was riding just for myself every morning 40 km for 5 months last year,then i stoped for 5 months because i moved and now want to ride again.i have a chance to ride a race and to be in lokal club.in my country there is no big number of raceing girls -just few.i want to try.people who saw me riding said that my cadence is great ,but they do not know how i feel when am i trying to ride hilly parts or to be above 33km/h.
i want to train for a race which is about 40km long .it is on 25th of march.as it is my 8th training this year on paths 40km long,i passed just about 300km.mostly i use small chain set(39).i ride training with recreative boys and to be stick with them i have to ride fast as they do ,and that brings me in 75-95% of my mhr.

ive always been led to believe that after your base miles the way toi bring on speed it interv als at max hr.everyone has their own theory re time/intervals.what worked for me one year was 1min on/4off x8.next session 2om,30ff,next session 3on 2 off,next session 4 on,1 off,with 8 reps each,20mins warm up and cool down,everyother day i did an easier rise of 2 hrs no real stress.im just finishing my base miles/endureance and will start intervals next month,at the moment im aiming for 21 hrs a week in the saddle,doing 10 mins on/off big chain ring for leg strength.

at the weekends i train with the lads as they tend to stretch me.i prob stay at 80% hr except days when im absolutely pooped,like monday av hr was 122.shows i was tired.keep a note of your resting hr.

This is what I have gotten from the cycling books that I have read. A lot of the training percents they give now are actually based on your Lactate Threshold (LT)and not Max heart rate. Just in case LT is considerd the highest heart rate you can maintain for 30 min to and hour with out fatigue.

It more specifically means the heart rate you can maintain without producing more lactate then your body can buffer in this time period. Then they set up the training zones based on that. I go buy anything under about 96% of LT is either recovery or endurance.

96% to 105% is the training zone where you usually time trial at while racing. This zone will help you gain the endurace to time trail and hold a pace at or slightly above LT. These can actually be used to help raise your LT. The last training zone is known as true zone 5, red line, I can't hold it long, it is more then 105% of your LT.

In my personal case this zone is anything above 200bpm or roughly 93% of mhr. And for everyone the actual heart rate numbers will be different but not the percentages of LT.

To race you will have to be able to spend time in the upper two zones. In fact you should train here twice a week or so after you put in your base endurance miles. Note in zone 5 six minuets seems to be considered a long interval, and if you are in the rate range it should be near impossible to do more then one or two at your riding level. These are very hard and painful as the ride goes on. Feel free to puke when riding here.