Beliefs

There is a lot of controversy around the topic of training and its duration. Most companies run 45min or 1hr sessions. Others are starting to promote 30min. training sessions.
Here are my thoughts:
So, science will dictate that people need to stay in their target heart rate zone for 45min-1hr. For optimal benefits for, weight loss, cardiovascular health and strength training.
-I happen to agree with this.
30 minute sessions:
peoples thoughts:
-you're not in the gym that long
-it's almost 45 minutes
-I still got a good workout (even though I could have done more)
-you can get on with your day
-its better than nothing...

I believe that if I take my normal 1hr. routine that I would give a fairly in shape client and make them do it completely in 30 or 45 minutes. Which means that we hustle and do not take many (if any) breaks. Which also means that you will definitely be in your target heart rate zone for the entirety.
Then you got your moneys worth and it did in fact benefit you.

TRUE STORY:
     You must shock your muscles and keep things changing to get the fastest and best results possible. Do a routine for 2 weeks then change it. Try new things. Switch up the duration of your workout. Try classes. If you do mostly weights I suggest you drop $100 on an unlimited month of TRX classes and do 2 or 3 a week. The other days you work out do your normal routine for that day.
Like life, if you do the same monotonous things every single day you get bored and become tired and have no energy. You get dull!
Try something new in your day and your eyes get opened again, things seem to be in a new light!
Switch your routines and your body will respond in the same beneficial and eager manner.