I will be turning 51 this summer and I have never backed off from PE. I buddy of mine turned me on to Beach Body's Insanity Workout. It's good old fashioned plyometrics, pushups, jumping, jumping jacks, running in place, etc. I feel like I am as fit as when I wrestled as a freshman in high school. Your entire body gets a work out. I changed up what I have been doing with Insanity and shortened it by doing what is described below with Phil Cambells
Peak 8 Work Out.
What makes this such an effective work out? First of all, it will cut your work out routines to fractions of what you think you need. You can do in the woods on your "retreat".
More important, it promotes your body to produce human growth hormone (HGH). HGH is one of the foundational biochemical underpinning that makes your strength training and everything else work like a efficiently to burn calories and keep yourself "young". I weigh about 180, so weight loss is not an issue for me. But for anyone interested in loosing weight, this works!
I watched a few videos about the "Peak 8" work-out routine. In a nut shell, it's like a high school sprinters work out. I ran track in high school and detested interval training because it was so hard. We ran quarter mile repeats and it was horrible. The peak 8 workout is more like running a 200 meter sprint. You run balls out for 30 seconds and then recover for 90 seconds. I never feel like puking like I did in high school. 30 seconds is perfect. Rinse and repeat 8 times and you are done. You can substitute any exercise of your choice for 30 seconds as long as you are going as fast as you can go to get your heart rate up. The goal is to get to 225 minus your age. In my case,that will be 225-50=175 beats per minute. I am ultra runner with a very low resting heart rate of around 40 beats per minute in the morning. Don't be surprised if hitting 225 minus your age hurts. Be careful when you start any routine.
Here is quote from the website:
How to Perform Peak 8 Exercises
Here's a summary of what a typical peak fitness routine might look like using a recumbent bike (although you can perform this on an elliptical machine or treadmill, or with any type of exercise you prefer):
" Warm up for three minutes.
Exercise as hard and fast as you can for 30 seconds. You should feel like you couldn't possibly go on another few seconds.
Recover for 90 seconds
Repeat the high intensity exercise and recovery 7 more times
Be mindful of your current fitness level and don't overdo it when you first start out. "
The benefits are astounding because you actually start producing your own Human Growth Hormone.