The concept of spot reduction has been around for so long that no one really knows where it originated, but countless studies have shown that while the theory sounds appealing, it's simply not possible – more on why later...
One of the earliest studies on this topic was conducted in 1971 by the University of California, where researchers Grant Gwinup, Reg Chelvam, and Terry Steinberg examined the thickness and circumference of subcutaneous fat on the arms of tennis players. Their theory was that the dominant arm would have significantly less fat than the non-dominant one due to varying levels of exercise over many years. Unfortunately, this was not the case, and the idea of spot reduction was debunked.
Fast forward 36 years, and in 2007, the University of Connecticut asked over 100 participants to complete a 12-week resistance training programme focused on exercising their non-dominant arm. The supervised training programme ended with an MRI scan, which revealed that fat loss was generalised throughout the body.
In 2013, the concept of spot reduction was revisited, this time focusing on the leg, following a similar setup to the 2007 study. After 12 weeks of intense training, researchers concluded that although the training programme was effective in reducing fat mass, the reduction was not localised to the trained body segment.
Why Protein matters in your ready meal?
Proteins are large, complex molecules that perform many vital roles in the body. It’s responsible for maintaining and replacing muscle tissue and plays an important role in the body's metabolism. Protein can also be a source of energy for the body when it’s not able to draw enough from calories. Eating high-protein foods also helps us to feel fuller, which can be a huge advantage when trying not to overconsume. This fuller effect happens because of Protein’s effect on the hunger hormone, Ghrelin. One study found that increasing protein intake from 15% to 30% of total calories led to overweight women eating 441 fewer calories a day, without having to restrict their diet. To conclude food that is “high in protein” can aid muscle recovery, provide emergency energy, and help us to feel fuller, which in turn leads to less overconsumption.
But wait… Could there be hope after all?
While the evidence overwhelmingly suggests that spot reduction is ineffective, a 2007 study published in the American Journal of Physiology Endocrinology and Metabolism indicated a different possibility. Researchers measured changes in fat mass and breakdown in tissues during high-repetition knee extensions, as well as blood flow. Test subjects completed 30 minutes of knee extensions with one leg on a low weight and then switched to complete 120 minutes with higher resistance on the other leg. The results showed that fat reduction and blood flow were greater around the more intensely worked muscle, suggesting that spot reduction might work – but only in very small percentages, comparable to a single grain of sand in a desert.
With spot reduction confirmed as nearly impossible, let’s delve into the nature of fat itself.
Understanding Fat – What Is It and Why Do We Need It?
Not all fat is created equal. In fact, there are two types of fat in your body – essential and stored.
Essential fat is stored in your organs, central nervous system, and bone marrow. You simply cannot live without this fat, as it is vital for proper organ function. Stored fat, on the other hand, refers to the fat that surrounds your organs to protect them from trauma, as well as the fat located just under the skin (subcutaneous fat).
Subcutaneous fat makes up the larger portion of stored fat in the body, and it’s the one we’re all keen to lose.
Our bodies evolved to store fat as an energy reserve. When we consume a surplus of calories, these excess calories are stored as subcutaneous fat, which can then be used as an energy source when blood sugar levels drop.
Why Do Women Have More Fat?
The difference in essential body fat percentages is because women, who may become pregnant, need an extra energy reserve to nourish a developing foetus. This stockpile is a natural preparation for potential future pregnancies.
Subcutaneous Storage Men and women tend to store fat in different areas of the body. Men are more likely to accumulate fat around their abdomen, while women tend to store it around the hips, bum, and thighs. However, this isn’t set in stone, as genetics also play a significant role in fat distribution. In fact, as much as 56% of your abdominal fat can be attributed to heritability, according to Pérusse, L. (1996).
The Best Way to Burn Fat
The difference in essential body fat percentages is because women, who may become pregnant, need an extra energy reserve to nourish a developing foetus. This stockpile is a natural preparation for potential future pregnancies.
Subcutaneous Storage
Men and women tend to store fat in different areas of the body. Men are more likely to accumulate fat around their abdomen, while women tend to store it around the hips, bum, and thighs. However, this isn’t set in stone, as genetics also play a significant role in fat distribution. In fact, as much as 56% of your abdominal fat can be attributed to heritability, according to Pérusse, L. (1996).
As mentioned, subcutaneous fat is used when blood sugar levels drop, and the body requires energy to keep moving. This demand for energy increases during exercise, which naturally boosts your ability to mobilise and metabolise fat.
Most people wonder whether to prioritise weight training or cardio for fat loss. The truth is that both forms of exercise offer benefits. Cardio can help burn calories, while strength training has additional advantages that cardio alone cannot achieve. Combining both cardio and strength training is the most effective approach to reduce your overall body fat percentage, revealing lean muscle definition.
LISS (Low-Intensity Steady State)
Low-Intensity Steady State cardio, like brisk walking, is known to be excellent for fat burning. Walking burns a higher proportion of fat per calorie than jogging because it utilises more oxygen, which is required to metabolise fat into energy.
HIIT (High-Intensity Interval Training)
High-Intensity Interval Training is efficient for time-conscious exercisers and may be “more effective at reducing subcutaneous and abdominal fat than other exercise types.” This is because it:
- Increases the resting metabolic rate for up to 24 hours post-exercise,
- Boosts levels of fat oxidation in the muscles,
- Suppresses appetite after exercise, and
- Improves insulin sensitivity.
It’s recommended not to exceed three HIIT sessions per week, as it can stress the body. Keep in mind that while promising, the research on HIIT and fat loss still requires further validation.
Strength Training
Strength training is highly effective for boosting metabolism, as the body continues to burn energy even after the workout – a phenomenon known as EPOC (Excess Post-Exercise Oxygen Consumption). Strength training helps to retain muscle mass, whereas excessive cardio may result in muscle loss. Additionally, larger muscles burn more energy, increasing the body’s resting metabolic rate.
It’s Not All About Exercise Fat loss isn’t solely determined by how you exercise; diet also plays a major role in how the body stores fat. Adopting a diet that cycles between "eat less, exercise less" (ELEL) and "eat more, exercise more" (EMEM) can help optimise fat metabolism.
The Bottom Line
While performing hundreds of crunches may strengthen your core muscles, it won’t specifically reduce fat over them. This is because the body uses energy from all fat stores, not from any one specific area.
By combining a well-structured diet with a balanced exercise routine that includes both cardio and strength training, you can reduce your overall body fat percentage and reveal toned muscles. Instead of focusing solely on isolated exercises, aim to increase your metabolism and build muscle to boost fat burning across the body.