GLP-1 Medications: What You Need to Know

I recently attended a conference session on GLP-1 medications and have increasing numbers of clients either taking them or interested in them. Having worked as a personal trainer for over 30 years, I’ve seen a significant shift in how we understand body size. 

 

Body size has traditionally been viewed as a balance between “energy in” and “energy out”. More recently, there has been a greater understanding of how an individual’s metabolic rate influences the energy seesaw. Metabolic rate is very individual, and some people are inherently disadvantaged.  Also, some people struggle with their relationship with food. Sometimes people are afflicted with both difficulties, and this has an impact on physical activity.  

 

The GLP-1 hormone suppresses appetite in the hypothalamus, reducing “energy in”. It improves metabolic rate by slowing how quickly food leaves the stomach, affecting the release of insulin and glucagon from the pancreas. The greatest implication for “energy out” is the requirement to do resistance training to make sure the weight isn’t all lost in lean muscle mass. 

 

Muscle drives glucose disposal, insulin sensitivity and metabolic rate. Without it, you’d lose a lot of the benefit of your medication and be more vulnerable to weight regain. Additionally, the loss of muscle and bone mass increases the risk of falls, fractures and general frailty. 

 

Being on a GLP-1 can make exercise more straightforward in some ways. The cost of the medication alone can be a motivator – if people are aware of the window of opportunity they are in to reset their metabolic rate, then getting to the gym often comes up the priority list. Many people find that without food noise, they have the space for building sustainable exercise habits. Seeing weight loss progress can make it physically easier to exercise. 

 

However, the medication can also interfere with an exercise habit. Side effects such as nausea, bloating, vomiting, diarrhoea, and constipation can make movement uncomfortable. Eating less can cause tiredness and dehydration. This can reduce training capacity and prolong muscle recovery. Not eating enough fibre can compromise gut health, and not eating enough protein can compromise muscle. Both these factors can reduce metabolic rate, contributing to the risk of can be factors in weight regain. 

 

Choosing medication also has psychological implications. The mechanisms involved in reducing appetite can create a possible reduction of dopamine and modulation in reward pathways. Some people report a lower reward drive across the board, with a sense of muted joy and a “greyscale” feeling. This doesn’t help with motivation to exercise, or any other element of the hard work required to lose weight. Also, if a person has been using food as a coping mechanism, then taking away their appetite to eat leaves them one coping mechanism short.

 

There are many reasons completely out of a person’s control that could cause them to regain the weight. As with any medication, everyone responds differently. A person could respond well initially, but there is always the risk of the body developing a tolerance. Sometimes people need to experiment with multiple drugs, and sometimes the side effects are just too difficult to manage. Any medication can experience supply issues, and if a person’s circumstances changed, they might not be able to afford to continue. There is emerging information about long term risks, and more will emerge over time.  

 

Consistent success on GLP-1 medication will likely come to those who carefully monitor their lifestyle and mood, and additionally have some good luck along the way. The commentary about GLP-1 medication being a quick fix is unfair. The only true short cut to being consistently skinny is having two skinny parents. Larger people are disadvantaged on many levels, and it’s positive that there are now more resources available to support change.