On Spot Reduction... fact or fiction?

Red flags might immediately go up when anyone claims that spot reduction - a training protocol to isolate fat loss from a specific body area through targeted exercises or similar - is possible. A great deal of past research has shown that the body tends to lose fat in general from the entire body regardless of whether a particular area is targeted with particular activities. However more recent research has shown that it may be possible to design a program that achieves spot reduction.

The scientific term typically associated with fat loss is lipolysis. Somewhat loosely, lipolysis is a metabolic process whereby fat cells are broken down for utilization by the body. The body stores fat in fat cells (adipocytes) all over the body but preferentially in particular areas (the abs, butt, and thigh regions) more than in other areas. However, when lipolysis happens, it tends to occur in a systematic fashion all over the body, and preferentially from areas with relatively more blood flow, as well as in areas where there are more beta receptor cells (relative to alpha-2 receptor cells).

There are receptors located on fat cells to which various chemicals in the blood stream bind to bring about metabolic processes including lipolysis. So with greater blood flow to any part of the body, there will be more of these chemicals being carried along. For lipolysis, catecholamines are the most important of these chemicals, being the main activators of the process. However there are different types of receptors (to which catecholamines bind) located on fat cells - beta-1, beta-2, beta-3, and alpha-2 receptor types, which regulate lipolysis. The beta receptors speed up lipolysis while the alpha-2 receptors tend to inhibit the process. The distribution of these receptors across gender, and body parts tends to be different and genetically determined.

This suggests three settings crucial to preferentially have lipolysis occur locally (i.e. spot reduction): The body has to be in a state of increased lipolysis, which is when the body is drawing on energy from fat stores; there has to be increased blood flow into that area (to move more catecholamines into the area to stimulate the process); and that area ideally has to have a high amount of beta (relative to alpha-2) receptors.

The third setting as noted already is somewhat genetically fixed e.g. alpha-2 sites are more than beta sites in the abs and thighs for most people, but the other two settings could be manipulated. The first could be activated by being in a fasted state (anytime baseline insulin levels are low from food deprivation, approximately around 4 - 5 hours after eating a regular sized meal) and by increasing the need for further fat loss through cardiovascular activity afterward. The second would be to preferentially force blood flow to the areas being targeted. This is where "spot strength training" would be necessary. When muscles in a body part are put through strength training with relatively high repetitions, there is increased blood flow into that area. It might be hypothesized that even if there are relatively high alpha-2 receptors in that area, that the consistent application of these two manipulations may be sufficient to still force preferential fat loss in that area, given the existence of some beta receptors there.

This seems consistent with research that suggests that while low concentrations of epinephrine (a type of catecholamine, and also known as adrenaline) inhibited lipolysis due to their high affinity for alpha-2 receptors, higher concentrations reversed this inhibition. It is also somewhat borne out anecdotally from some sports which tend to combine both cardiovascular work with rigorous training on specific body parts, and where there appears to be spot reduction in those areas for athletes of all stripes.

So how could this be implemented? It has been suggested that, while in a fasted state, immediately following a targeted high repetition strength training in the focal area say the abs, or thighs or butt or back of the arms, that cardiovascular exercise with heart rates in the 65-75% MHR range be carried out for about half an hour: The body is already in a state of lipolysis, and with the strength training, there is increased blood flow into the target area bringing more catecholamines which would, despite the inhibitions from alpha-2 receptors, yield net lipolytic effects in that area, preferentially, relative to the rest of the body. The intensity of the cardio is designed to increase the body's fat burning needs while still prioritizing blood flow in the target area.

My back of envelope thoughts are that one main reason why it has been difficult to find evidence for spot reduction in prior studies is due to the genetically determined distribution of alpha-2 and beta receptors, where interestingly the former (which inhibits lipolysis) are relatively more in the areas we want to lose fat from the most, for most individuals. Given this, it follows then that trainees are perhaps not in a sufficiently fasted state to begin with, or they do not design their cardio session after or along with, as opposed to prior to, their spot strength training session, and at the right level of intensity, to induce high concentrations of catecholamines into that area.

One suggestion, in the spirit of the research that demonstrates it works, is one that I have used myself with positive results: While in a fasted state, carry out a preferred form of cardio that allows you to combine moderately intense cardio with an active contraction of the muscles in the targeted area. For example, if abdominal fat loss is desired, while using an elliptical machine, and with a very high level of resistance and incline, contract the abs forcefully through each cycling motion for periods of 1-2 minutes, and a 1 minute rest period, and for a total 10-15 minutes, then cool down with more regular lower intensity for the next 5-15 minutes, still maintaining a slight contraction.You can see that this seeks to achieve the process for increased lipolysis in a specific area, in this case the abs, to preferentially burn fat stores in that area for energy.

What about the possibility of associated muscle loss? There are things that can be done to mitigate this. I think for the case of the abs or any targeted area, the strength training being done will induce hypertrophy, which will tend to prioritize muscle tissue repair and growth in that area during the recovery period, which should include sufficient protein intake in one's post-workout meal. Further, by keeping the moderately intense cardio to just 10-15 minutes and by continuing in a less intense phase, muscle loss should be limited or negligible, if any.

OK, this is how it could pan out in practice. Suppose you dedicate 60 - 90 minutes in a day to workout and suppose you follow a push-pull-legs routing for three days on and one day off. On each of your training days you may do a warm up or stretch, then go into your main workout for about 30 - 60 minutes. It may be ideal to have eaten some 2-4 hours prior so that you have energy to power through your workout, and get your body eventually into a depleted (fasted) state from your workout, then you implement the strategy as outlined above. If you are not going to be able to do the suggested targeted area muscle contractions during the cardio session, then make sure to dedicate the last 5-10 minutes of your main workout to working out that specific area muscle with lots of repetitions just prior to your cardio session.

So the bottom line is spot reduction may not be fiction after all. Give this a try and let me know how it works. Remember you need to be patient, and also realize that this will take a lot of discipline and intentionality on your part.

Abiye, NASM-CPT, CNC

Regal Lifts (regalifts.com)

IG: @regalifts