Spot Fat Reduction Confirmed?! by Lou Degnan

Spot Fat Reduction Confirmed?!

One of the many questions I’ve been asked by my patients here at PLC is whether or not we can burn off stubborn belly fat specifically. As much as I’d like to believe we can, my answer is always a resounding “Unfortunately, no.” Through my extensive schooling in kinesiology and exercise science, I’ve always been taught that where exactly lipolysis occurs is completely up to our genetics, our gender, and our age; with exercising having no influence. The reasoning is sound:  fat is stored all over our body and serves as an energy reserve; not for aesthetic purposes. Unlike muscles that have specific actions to perform, all fat stores function practically the same. 

This conclusion never sits well with patients but frankly, it has never sat well with me either. Even before cosmetic surgeries became more popular, I had a hard time believing in what I was selling. How could there be so many discrepancies between even the fittest physiques from uncontrollable factors alone?  

A 2022 meta-analysis compared  13 studies found that localized muscle training did not affect localized fat deposits.  When looking deeper into these studies, I believe many of the testing methods were answers to the wrong question.  Experimental group protocols ranged from performing an impractical number of bodyweight abdominal exercises (5,000 sit-ups over 27 days) to performing unrelated resistance training entirely (heavy leg press on a single leg 4x per week for 12 weeks.   Despite the research seeming conclusive, the field of exercise science continues to question the possibility of spot fat reduction. Finally, in late 2023, a study was published with promising results:  

Researchers tested abdominal fat reduction in two groups of clinically overweight men: the experimental group performed moderate intensity steady state cardio (27 minutes at 70% Max heart rate) combined with resisted abdominal exercises ( 4x 4 minutes of trunk rotation and abdominal crunches at 30-40% of 1 Rep Maximum).  Essentially, the study looked to see if performing some cardio before specific strength training exercises had any effect on fat metabolism as opposed to just steady-state cardio. These groups were tested pre and post-intervention for abdominal fat via a DEXA, a device that measures bone density as well as body composition that we happen to have here at PLC. 

The results were shocking, to say the least. While both groups lost a similar amount of total body fat, the experimental group ( short, moderate intensity cardio before specific ab strength) saw their abdominal fat decrease 2.5x more on average than the cardio-only group. The control group (cardio only) also saw more fat reduction in their legs than the experimental group.   Because of this discrepancy, this seems to confirm the idea that spot reduction is possible when 2 things occur: 1. Fat cells are mobilized by increased blood flow from cardiovascular exercise, and 2. Performing area-specific strength training exercises while still in the “fat-burning” heart rate zone.  

This was the first study of its kind to control energy expenditure; meaning both training protocols required the same amount of calories burned. That’s why the abdominal resistance training protocol seems so unorthodox compared to what people typically think of when training the abs. Do I expect you to perform 4 sets of 4 minutes straight of resisted crunches and twists after a half an hour jog? No. But the concept of moderate-intensity cardio first, specific resistance exercises immediately after is certainly worth exploring further thanks to this study.  Here is a more practical example of what this study suggests: 

4x per week

Treadmill incline walk or jog @ 70% Max HR for 30 minutes

Alternating Dumbbell Side Bend 4x 12 – Return to upright position after each rep

Abdominal Crunch Machine  w/ eccentrics 4×12 –  slow and control the movement on the way back to the starting position

Machine Trunk Rotation 4×12 – Perform 4 sets on both sides