how can i lose weight with out lossing muscle

This is true as stated, but could be misleading. Your body doesn't really store protein, it uses it to build body tissues. There is a huge amount of misinformation about "burning muscle/protein" as a fuel source. The truth according to current physiology and biochemistry research is that the body spares and recycles protein whenever possible.

As part of its normal regeneration process, your body is constantly breaking down damaged cells into amino acids which are then reutilized by the creation of new peptide bonds to make new proteins for construction of new tissue. This cell turnover is very necessary to maintain healthy tissues. The slowing of this process is one of the components that causes physiological decline associated with aging.

When carbohydrate reserves are exhausted, the liver can convert proteins into fatty acids, ketone bodies, or glucose. Before amino acids (the building blocks of protein) can be catabolized, they must be converted into substances that can enter the Krebs cycle for oxydation, or converted to glucose/glycogen. The process of converting amino acids into carbohydrate (glucose) is called gluconeogenesis. It is actually rather difficult for the body to convert protein to carbohydrate in order to burn it. It only happens in significant quantities in two situations, during extreme high energy demand when glycogen and blood glucose are exhausted but before fat stores (lipids) can be converted into glyceraldehyde and then to glucose, or, in periods of starvation when both carbohydrate and lipid stores are exhausted.* The first proteins to be utilized are the free proteins and amino acids in the blood. The body will not cannibalize (notice the distiction from catabolization) healthy muscle or vital organ tissue exept in extreme circumstances.

Another cause of muscle loss is atrophy due to disuse, such as is seen when muscles are immobilized in a cast for an extended period. Some illnesses can also cause muscle wasting. Overtraining without adequate recovery also interferes with muscle growth and repair.

So, as long as you have decent nutrition with normal glycogen and glucose stores, have some non-essential bodyfat (above 5% or so in adult males) and adequate dietary protein, you will not "burn" significant amounts of muscle tissue as the result of resistance training or aerobic exercise. You still need to allow adequate recovery time based on your own physiology to avoid overtraining.

*Source: Advanced Principles of Anatomy and Physiology by Tortora and Grabowski, Harper Collins Press

I don't mind at all. Glad you found the post useful.

I should add that excess protein can be converted to lipids (fat) for storage, though not as readily as fats and carbohydrate. It is possible to get fat even on a very high protein diet if you consume too many calories.

Softgainer,

I respectfully disagree. From what I have learned and observed over the years, the shortcut should look more like this:

weight resistance training > muscle fiber damage > nutrients and regeneration needed > sensible cardio results in increased blood flow bringing nutrients and oxygen to regenerating tissues and clearing waste products of muscle fiber damage and repair > muscles have everything they need to regenerate and produce larger stronger muscle fibers > rest > repeat

Omitting cardio also assumes that your goal is simply mass and strength at all costs, rather than optimum health. Remember that the entire purpose of the cardiovascular system is to get oxygen and nutrients to all of the cells of the body and to transport waste products away for elimination. If shipping and receiving isn't up to par, the factory shuts down.

The heart is a muscle and deserves it's spot in the rotation just like your lats and biceps.

IMHO,

MedX

i've posted this before, yet i'm more than willing to argue this till the moo cows come home

your body doesn't strictly go into catabolic or anabolic "states", it performs catabolic and anabolic actions.  your body is always breaking things down, just as it's always building up.  you can build muscle while performing exercises that exert quite a bit of energy.  does your body stop producing hormones while on an energy deficit? no. does the whole class stop for one kids to sharpen his pencil? no. you don't think your body can multi-task?

you can use energy to exert yourself running, which may lead to an energy deficit, but as long as you're giving your body means to replenish this energy stores you should be fine, as long as you're giving the body reason to maintain/gain muscle through resistance training.

you forgot one small thing. with cardio training you want to trigger a change in your cardio vascular system. as with hypertrophy the body needs to be stimulated and get the time to make the changes afterwards.

i think it is routine depending if you need cardio. scoobys 30-60 minute superset routines should actually be enough stress on the cardio vacular system for 3 days including the workout day.

but when you do HIIT cardio the heart rate is dropping in some intervals too.

dno how far it should drop.

small side note: you should warmup for intense cardio units like fast rope skipping, fast swimming or HIIT

Just do cardio.  I don't know where such an idea as 20 minutes of cardio ruining all the progress you have made in years came from.  No person educated on the matter would ever tell you that, unless they wanted to make you look like a fool.

This is a body building forum.  Body builders do cardio.  Obviously cardio does not make you shrivel up into a little stick.