What is the Best Workout for Weight Loss?
- There is no "best" workout for fat loss.
- Exercises isn't an efficient method of losing weight, unless you exercise four to eight hours each day.
- Diet is the main driving mechanism of weight loss, not exercise.
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To address this question - what is the best workout for weight loss - let's consider the following points.
When Looking for the Best Workout for Weight Loss
#1 - Exercise Burns Few Calories
When someone decides it's time to lose weight, their first instinct is to increase activity levels. While this is certainly a good thing for metabolism and longevity, exercise actually burns very few calories compared to a slight calorie deficit.
20 minutes of steady state cardio, typically grinding it out on a treadmill, burns about 100 calories. This is for an average weight individual who is walking about 3 miles per hour. We'll use this as a baseline. Calories burned per session could be slightly higher or lower depending upon the speed of the walk and the weight of the cardio bunny.
Perform three of these sessions per week, and you burn 300 calories. This equates to 15,600 calories burned per year, and a measly 4.46 pounds of fat lost. That's it. Bump this up to four sessions per week and you burn a stunning 5.94 pounds of fat per year.
Now, let's compare this rate of weight loss to a slight calorie deficit. Nothing radical here. We are going to drop your daily calorie intake to 300 below maintenance levels. This means you are eating slightly fewer calories than required to maintain your weight.
A 300 daily calorie deficit burns 2,100 calories burn week, or 109,200 calories per year. This is a loss of 31.2 pounds of fat.
Even if you dramatically increase cardio to 5 hours per week, you're still only burning 22.29 pounds of fat. This is a huge time investment for limited return. Go crazy "dramatic" and drop your calories to 500 below maintenance, and you lose 52 pounds of fat per year.
The point here is simple... Use cardio for health and a slight metabolic boost, but focus on diet as a primary weight loss mechanism.
#2 - The Best Workout is the One You Enjoy DoingNow that we have established that exercise is not an efficient way to burn fat, the question becomes: Which workout is best for weight loss?
Personal trainers love to punish the people that hire them. Soreness and vomiting are seen as sick badges of honor. This approach to exercise is idiotic. You do not need to beat up your body to see results. In addition, punishing styles of training are demotivational.
How many people quit going to the gym because they hate their workouts? A lot.
Two things you must consider. First, the best workout for weight loss is the one you'll stick to. Find a resistance training protocol that you actually look forward to. Pick a form of cardio that is engaging. It doesn't really matter what training program you use, as long as you get stronger than you are now and remain consistent.
Second, exercise doesn't need to be punishing. Not in the least. This style of working out is simply fire and thunder. It looks impressive, but isn't required in the least to burn calories or build muscle.
All that you really need is progressive overload and consistency. Period, end of story.
#3 - Limiting Rest Between Sets to Maximize Calories Burned and HormonesNow here's some good news. There is a method of training that is pretty darn good for kicking your metabolism up a notch. It's also decent at boosting your testosterone levels. What is this magical, mythical form of training involve?
Restricting rest in between sets.
In this day and age, we have become slaves to our smart phones. It's not unusual for us to check our screens in between sets. While this might be a good way to fill the downtime, it's awful for our metabolism.
When you limit rest in between sets to 30 to 60 seconds, your heart rate stays elevated. This helps to burn more calories, and turns our resistance training sessions into programs that also aid with fat loss and heart health.
But will this style of rest-pause training hinder the muscle building process? No, in fact it's an excellent way to train. Not only do you continue to beat a muscle while it's down, but testosterone levels also increase.
In one study, 60 second rest periods were shown to be superior to 2.5 minute rest periods during the first five weeks of training.  A second study revealed that rest-pause training elicited elevated higher levels of total and free testosterone. 
References1) "The Effect of Resistive Exercise Rest Interval on Hormonal Response, Strength, and Hypertrophy with Training. - PubMed - NCBI." National Center for Biotechnology Information, www.ncbi.nlm.nih.gov/pubmed/19077743.
2) "Long Rest Interval Promotes Durable Testosterone Responses in High-Intensity Bench Press. - PubMed - NCBI." National Center for Biotechnology Information, www.ncbi.nlm.nih.gov/pubmed/26466135.