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Stimulant vs Non Stimulant Pre-Workout

Stimulant vs Non-Stimulant Pre-Workout (Which Is Best)

Pre-workouts are a super popular product that can help you to push your workout to the next level and maximize gains. Pre-workouts come in different forms including pills and powders. They also vary significantly in the ingredients and the number of different ingredients that they contain. 

A key difference between pre-workout products is whether or not they contain a stimulant. Some pre-workouts contain stimulants, most commonly this stimulant will be caffeine, but yohimbine or ephedrine are also sometimes used. Then there are pre-workouts that don’t contain any kind of stimulant, also known as ‘stim free’ products.

A commonly asked question is which pre-workout is better, stimulant or non-stimulant? We are therefore going to compare the two in a stimulant vs non-stimulant pre-workout test.

Here I’m going to explain the difference between stimulant and non-stimulant pre-workout products and evaluate their pros and cons so you can decide for yourself which is the better option for you.

How Does Stim-Free Pre-Workout Work?

Stim-free pre-workouts work through nitric oxide, which has been shown to improve the delivery of oxygen to muscles and increase vascularity through opening up the blood vessels. This increase helps to combat fatigue as well as promote muscle growth and recovery.

To expand on this a bit more, pre-workout products containing stimulants like caffeine, yohimbine, or ephedrine work by increasing energy levels. They do this by affecting the body’s central nervous system leading to increased levels of focus and alertness, increased heart rate, and decreased sensitivity to fatigue.

In comparison, stim-free pre-workouts work by increasing nitric oxide. Nitric oxide has been shown to increase the delivery of oxygen to muscles by opening up blood vessels. This helps to stop the build-up of lactic acid meaning you can work out for longer without feeling fatigued.

This increased level of nitric oxide also means increased blood flow to muscles, also known as increased vascularity. This promotes muscle growth by transporting essential nutrients to muscles as well as oxygen. It also helps to promote muscle recovery, reducing soreness after working out.

Check out this video on the benefits of using stim-free pre workouts: 

Stimulant vs Non-Stimulant Pre-Workout Compared

When deciding between stimulant and non-stimulant pre-workout products there are different factors to consider. I’ve broken it down into the main issues people have with pre-workout products (energy levels, side effects, and flexibility of use) to evaluate the pros and cons of each so you can decide which is best for you.

Energy Levels

The main thing you’re probably concerned with when deciding between stimulant or non-stimulant pre-workout products is which offers the best results. 

For energy levels, pre-workouts containing stimulants definitely have an advantage. Stimulants like caffeine interact with the body’s central nervous system to block what’s known as adenosine receptors. When you have high levels of adenosine you feel tired and fatigued, so caffeine helps to combat these feelings leading to higher energy levels.

Most of you will be familiar with the buzz of energy that hits around 30 to 45 minutes after using pre-workouts. It’s this buzz of energy that stimulants cause and it’s incredibly effective for helping to power through a tough workout.

Stim-free pre-workouts don’t contain a stimulant that will trigger a big release of energy. Instead, they help to fight fatigue by increasing nitric oxide levels and helping to deliver more oxygen and nutrients to your muscles.

However, with stim-free pre-workouts, you don’t experience that same buzz of energy that you do with the ones containing caffeine. So although stim-free pre-workouts have other pros, if it’s a big increase of energy you’re looking for then stimulant pre-workouts are a better option.

Side Effects

Pre-workout products can cause side effects. These will vary from person to person and depend on the ingredients within different pre-workout products. Most of the time though when people complain about side effects from pre-workout supplements it’s to do with stimulants.

Pre-workout products containing stimulants often cause side effects because of the stimulant. For example, caffeine can cause a lot of side effects including shaking, heart palpitations, as well as sleep disturbance, and insomnia. Caffeine can also affect your digestive system making you need the toilet.

These side effects are a result of how the stimulant interacts with the central nervous system and they usually go away as the caffeine is metabolized by your body over a period of 6-12 hours. Although they’re often short-lived, these side effects can have a big impact on day-to-day life and they obviously aren’t ideal when you’re trying to focus on a workout.

Most people also build up a tolerance to pre-workout through excessive dosages which blunt receptiveness by the body. This eventually leads to pre-workouts no longer working

In comparison, stim-free pre-workouts don’t cause the same side effects as they don’t contain ingredients like caffeine. As a result, they shouldn’t cause insomnia, shaking, or heart palpitations (or any of the other common side effects we see as a result of caffeine). 

Overall then stim-free pre-workout products are a better option in terms of experiencing fewer side effects. You know your body better than anyone so if you experience side effects from stimulants or are worried about potential side effects then I’d recommend going with a non-stimulant pre-workout product.

Flexibility of Use

Something else to consider when deciding between stimulant or stim-free pre-workout products is the flexibility of use. As I explained above, pre-workout products containing caffeine can cause insomnia and disturb sleep. 

As a result, it’s usually recommended that you use these products much earlier in the day like in the morning or early afternoon. This gives your body time to metabolize the caffeine, which will hopefully reduce the likelihood of it negatively affecting your ability to sleep. However, this can be pretty restrictive especially if your only time to workout is later on in the day. 

In comparison, as stim-free pre-workout products don’t cause sleep disturbance they can be used at any time without having to worry that you’re going to be awake all night. So if you’re looking to work out later on in the day, then stim-free pre-workout products are going to be the better option.

Overall then stim-free pre-workout products are more flexible in terms of when in the day they can be used. 

When to Take Stim-Free Pre Workout

As they don’t contain stimulants that can cause sleep disturbances and insomnia, stim-free pre-workouts can be taken at any time of the day. Like stimulant pre-workouts, they should be taken 30 to 45 minutes before a workout in order to be absorbed before working out.

Can You Stack Stim and Non-Stim Pre-Workout?

Stimulant and non-stimulant pre-workout products can usually be stacked together, allowing you to make the most of the benefits of both products. When stacking though,  check out what ingredients these products contain to make sure you aren’t doubling the dose of an ingredient.

Stacking products is a great way of maximizing the benefits that different products contain. With pre-workout products, staking a stimulant-containing product and a stim-free product allows you to get the benefits of both. 

Also by not taking as high a dose of a product containing stimulants, you shouldn’t experience as many, or as intense, side effects and there’s more flexibility in what time of day you take it.

So if you’re struggling to decide between stimulant and non-stimulant, pre-workout stacking is a good option. This is typically done by using half of your stimulant product and half of the stim-free one and taking it in the usual way that you would have a pre-workout. 

The only thing to make sure of is that these products don’t contain the same ingredients as you could end up overconsuming an ingredient and end up with serious side effects, so always check the labels.

Overall Verdict

When it comes to deciding between stimulant or non-stimulant pre-workout there are pros and cons to each. 

The main advantage of stimulant products is that they can give you a huge boost of energy which is great when doing an intense workout. If you struggle with energy levels when working out, pre-workouts containing stimulants are probably your better option.

However, stimulant pre-workout products come with side effects because of the stimulant that they contain. Commonly reported side effects include sleep disturbance, gastrointestinal problems, and shaking. As a result of these side effects, this makes them less flexible too in terms of what time of day you should take them. 

In comparison, stim-free pre-workouts work differently but can be just as effective for helping you achieve workout goals. They’re also less likely to cause side effects and are therefore more flexible to use. So overall this makes them a good choice for most people.

If you really are struggling to choose between the two though, stacking stimulant and non-stimulant pre-workouts is a way to maximize the advantages of both products and minimize the downsides.