Written by Garett Reid | NSCA, CSCS, CISSN, M.S.E.S.S
Fact checked by Tyler DiGiovanni, BSBM
FACT CHECKED
“How can I lose belly fat?!” This used to be the question that all the experienced lifters scoffed at, as only newbies would ask it. Everyone knows you can’t choose where you lose fat, and merely asking about it can instantly cause others to look at you differently.
Well, that may be an exaggeration, but you get the idea.
But get this: What if we told you this question isn’t as silly as we think? In fact, several studies show it may be possible.
Yes, not just one study, but several. Even more interesting is that they all follow a similar protocol based on the same theory, demonstrating some replication!
In the world of science, replication is a key component to the scientific method to demonstrate a result isn’t a fluke. When a study is successfully replicated, it provides substantial evidence to its legitimacy.
So what is this theory?
Let’s first go through a summary of the studies.
Study 1
The first study was conducted in 2017 and split sixteen sedentary women into two groups. These two groups of women then completed an 8-week training program.
The first group performed an upper-body resistance program followed by 30 minutes of lower-body cardio by cycling. The second group performed a lower-body resistance program followed by 30 minutes of upper-body cardio on an ergometer. Other than this, all other variables were similar.
After 8 weeks, the results showed that the upper body resistance group saw more fat loss in the upper body while the lower body resistance group saw greater fat loss in the lower body.¹
Study 2
The second study, conducted in 2021, had 14 participants split into two groups: a spot reduction group and a traditional group.
Both groups performed a program consisting of the same exercises and rep scheme. Another important aspect is the exercises consisted of a mixture of endurance (stair stepper, bike, treadmill), strength (bench press, lat pulldown, leg press, etc.), and core (crunches).
The only thing that was different was the order in which the exercises were performed. The spot reduction group performed the cardio and core exercises first as a large circuit. They then performed the strength exercises in successive order at the end.
On the other hand, the traditional group performed all of the exercises in successive order. They first completed the endurance exercises in succession and then did the same with the strength exercises.
At the end of twelve weeks, the researchers found that the spot reduction group had significantly greater fat loss around the abdomen along with a greater total BMI reduction!²
Figure 1: Paoli, Antonio, et al. (2021)
Study 3
And finally, study 3, which is probably the most impressive. Conducted in 2023, 16 overweight men were placed into two groups; a spot reduction group and a control group. They then followed a 4-day training program for 10 weeks.
The control group simply performed 45 minutes of cardio on the treadmill every session. Easy peasy.
On the other hand, the spot reduction group first performed 27 minutes of cardio on the treadmill. They then performed two different machine-based core exercises, torso rotation and crunches. Sounds simple enough but there was something peculiar in the way they performed them; this will be important later.
Instead of using a traditional strength protocol (e.g., 3 X 12), they performed these exercises in an endurance fashion using four 4:00 intervals.
When performing the torso rotation, they would train twisting in one direction for 4:00 at 30-40% 1RM. They then performed the other direction for 4:00, which acted as recovery for the other side. This was repeated for two cycles for a total of 16:00.
When performing the crunches, they again performed four 4:00 intervals using 30-40% 1RM, split with 3:00 of recovery using 20% 1RM for a total of 25 minutes. When added together, the treadmill and core exercises totaled 57 minutes of training.
One important aspect is that the researchers chose these times so that both groups burned the same amount of calories.
At the end of the 10 weeks, both groups lost a similar amount of fat mass. However, the spot reduction group lost almost 2.5x more belly fat compared to the control group (2.6lbs vs 1lbs)!
So if both groups lost the same amount of weight but the spot reduction lost that much more around the belly, where did the treadmill group lose fat? Well, while not a lot, it is interesting to see that the treadmill group did lose slightly more around the legs!³
Figure 2: Mathias Forsberg Brobakken, et al. (2023)
What’s Going On?
Traditionally, when someone tries to reduce fat around their core, they perform a lot of crunches and other core exercises while using traditional strength protocols.
For example, they may do 3 sets of 15 reps. However, this thought is misplaced as it is designed to build muscle!
Researchers have noted this, so they decided to use abdominal exercise differently. Rather than trying to build muscle, they wanted to use core exercises to elicit another reaction, fat mobilization, and increased blood flow.
When the body needs energy from fat, it doesn’t matter where it comes from. For example, if you’re running, your body can use fat stores from your belly or arms to provide energy.
However, the researchers theorized that the body will break down fat from the area of least resistance if possible.
Increased Blood Flow & Close Supply Of Fat
It’s important to understand that increased blood flow is crucial for fat breakdown for a number of reasons. To begin with, blood delivers various nutrients and hormones essential for fat breakdown to the area while also helping to remove metabolic byproducts.
More importantly, blood flow has been shown to actually play a role in stimulating fat breakdown.
At the same time, they also theorized the body would pull from the closest area to the working muscle, assuming it’s easy. For these two reasons, the researchers decided to use endurance training for their spot reduction.
Performing core exercises in prolonged fashion would increase blood flow to the stomach. At the same time, as we discussed earlier, it’s theorized that muscles will attempt to draw energy from surrounding fat stores.
Since the core muscles being worked are near the belly fat, it was theorized this would encourage it’s break down!
So, this was the basic theory. Endurance training.
Our Analysis
There’s one important piece of information to keep in mind. For whatever reason, the spot reduction appears to only occur in the belly area. Other areas have been tested but have not yielded results. With that said:
While spot reduction does seem to occur in these three studies, they do have some limitations.
They’re not exactly the same.
For example, in the first study, the area that used strength training in the upper body saw a greater decrease of fat in the upper body, while the lower body strength group saw more fat loss in the lower body.
However, the other two studies proposed that endurance training would be the mechanism for fat reduction.
Another difference is seen between studies 2 and 3. In study 2, they used circuit training, yet the core exercises were performed with just 20 reps at a time. In contrast, study 3 had participants train the core for a total of 32 minutes continuously at low intensity.
So while they both used the concept of endurance training as the primary driver, it was done in a different manner.
Does the core need to be trained continuously as in study 3?
While we can’t say for sure, it does suggest that the endurance aspect along with core training, whether continuously or intermittently, plays a crucial part.
How To Apply To Your Program
While an exact protocol needs more research to be defined, there does seem to be enough to make some general suggestions.
The first piece of the puzzle wasn’t mentioned in the studies but we think it holds merit. If fat utilization is the key to spot reduction, it makes sense training fasted would yield greater results.
Training fasted would be ideal as your glycogen stores are depleted increasing the need to utilize fat. To be clear, this is just an observation and a guess based off of what we see!
With that said, there are two protocols you could try. The first protocol would be to perform a circuit of cardio exercises and core exercises. This may look like:
- Cycle 5 min
- Treadmill 5 min
- Crunches
- Cycle 5 min
- Treadmill 5 min
- Core Rotation
- And so on...
Look at this as a blueprint. You could alter the exercises and time based on your preferences.
The second protocol you could attempt is to first perform cardio for 20-30 minutes. This would then be followed by core work in an endurance fashion. We like the idea of using a crunch machine with low weight and Russian twists performed with a very light weight or even body weight.
- Treadmill 20-30 min
- Crunches @ 30-40% 5:00
- Russian Twist 3:00
- Crunches @ 30-40% 5:00
- And so on
Again, this is a basic outline, so you can adjust as necessary. One issue here would be “hogging” the machine. Theoretically, any core exercise would work so long as you can perform it for extended durations.
Final Say
While we’re not ready to say, “Go do it! It works for sure!” we think there’s enough information to give it a shot. There’s enough research, as well as theory, that suggests plausibility. Plus, when you consider the worst thing that will happen is you burn fat everywhere rather than your belly, it seems like a no brainer!
References
- Scotto di Palumbo, Alessandro, et al. “Effect of Combined Resistance and Endurance Exercise Training on Regional Fat Loss.” The Journal of Sports Medicine and Physical Fitness, vol. 57, no. 6, 2017, pp. 794–801, www.ncbi.nlm.nih.gov/pubmed/28497942, https://doi.org/10.23736/S0022-4707.16.06358-1.
- Paoli, Antonio, et al. “Effect of an Endurance and Strength Mixed Circuit Training on Regional Fat Thickness: The Quest for the “Spot Reduction.”” International Journal of Environmental Research and Public Health, vol. 18, no. 7, 6 Apr. 2021, p. 3845, https://doi.org/10.3390/ijerph18073845.
- Mathias Forsberg Brobakken, et al. “Abdominal Aerobic Endurance Exercise Reveals Spot Reduction Exists: A Randomized Controlled Trial.” Physiological Reports, vol. 11, no. 22, 1 Nov. 2023, www.ncbi.nlm.nih.gov/pmc/articles/PMC10680576/, https://doi.org/10.14814/phy2.15853.
Garett Reid
Author