10 Things You Should Never Do Before A Workout (Learn Why)

James Cunningham, BSc, CPT
Published by James Cunningham, BSc, CPT | Staff Writer & Senior Coach
Last updated: April 1, 2024
Our content is meticulously researched and reviewed by an expert team of fact checkers and medical professionals. They ensure accuracy, relevance, and timeliness using the latest reputable sources, which are cited within the text and listed at the end of the article. Before publication and upon significant updates, we confirm factual accuracy, committed to providing readers with well-informed content. Learn more.

I've been in the fitness world long enough to understand that the success of any workout depends on what you do beforehand.

You can do specific activities that seem like normal behavior, but they buffer your gym progress.

To ensure I succeed in my fitness goals, I solicited advice from my personal trainer to understand what pre-workout habits I should avoid doing.

Here's a summary of my findings.

Quick Summary

  • Before a workout, it's important to avoid cutting down on sleep, skipping warm-ups, working out without a plan, eating heavy meals, drinking too much water or caffeine, over-moisturizing your skin, taking anti-inflammatory medication, doing intense sets back-to-back, and consuming alcoholic drinks.
  • Caffeine is good for energy, but when taken in excess before a workout, it can cause irritation and dehydration.
  • According to the Havard School of Public Health, a big meal can cause distress and abdominal discomfort when doing intense workouts or cardio.
  • Based on my experience, tailoring your pre-workout routine to your body's needs is the key to unlocking your full fitness potential.

10 Things to Avoid Before Working Out

Not having enough sleep

Here are ten things you need to steer clear of to reap the most benefits from your fitness session.

1. Cut Down Sleep Time

Inadequate sleep harms athletic performance, a fact I've seen firsthand with my clients.

One of my clients consistently struggled with early morning workouts until we addressed their sleep routine. Once they prioritized getting enough sleep, their performance improved dramatically.

This aligns with research from the Journal of Science and Medicine in Sports, which states that sleep deprivation reduces fitness efficiency because working out feels more difficult [1].

Plus, it's a double whammy: poor sleep slashes muscle recovery and drains your energy, both big deals for nailing a workout.

Bottom line? A solid night's zzz's is just as key as the workout itself for top-notch results.

2. Skip Warm-ups

A person holding towel behind his neck

Dodging warm-ups? Big mistake. Saw a client get sidelined for weeks with a muscle strain from it.

Turns out, skimping on joint and muscle prep is a top reason for serious strains – Sports Medicine studies confirm it [2].

The fix? Get your body ready with some static stretching first. Always kick off with a few minutes of dynamic stretching for peak performance.

Relaxing too much? Your muscles tighten up as per research published by the National Library of Medicine [3]. Try light cardio or foam rolling to boost blood flow and oxygenate those muscles.

And don't forget to throw in some weight dynamic stretches. They're great for getting your muscles primed and injury-free, plus they amp up your overall performance.

3. Workout Without a Fitness Plan

Exercising without a plan is something I always advise against.

It's a bad idea to exercise without a strategy, as you'll be wasting time hopping from one piece of equipment to the next.

Psychological preparation is key. Techniques such as visualization and setting clear goals before your workout can significantly enhance your focus and performance, making your gym sessions more effective and enjoyable.

Start by setting aside upper and lower body days, including leg day exercises. Then you can add specific pull, push, and stretching exercises for each workout.


4. Eat Heavy Pre-Workout Meals

A woman holding a dumbbell and a bowl of meal

From my experience, eating heavily before a workout is a no-go for me and my clients. It's a fast track to 'stitches' and feeling like a sloth.

Eating huge fatty and fiber meals can cause bloating because fat and fiber take way more time to metabolize and get absorbed in the digestive system.

Harvard School of Public Health says heavy meals and intense workouts don't mix, causing gut woes [4].

Also, watch out for exercise-induced anaphylaxis (EIA) – it's a real thing if you eat the wrong stuff before exercising, as the University of Rochester points out [5].

“Your pre-workout habits can set you up for either an effective or ineffective workout."

- Dempsey Marks, Personal Trainer

As a personal trainer, I always advice my clients to go for a light, nutrient-packed snack like whole wheat bread rolls, fruits, veggies, or a protein shake.

Got EIA? Skip the trigger foods and chat with your doctor for advice.

Related: Should I Eat Before or After a Workout?

5. Drink Too Much Water

Close up image of a water bottle

Drinking excess water before working out can make you feel queasy, create cramps, or want to end the session early.

According to research published by the National Institutes of Health, you may also increase your risk of hypernatremia, an uncommon but severe illness, by attempting to chug down a gallon before hitting the gym [6].

Also, with excess body water, the kidneys cannot handle the fluids quickly enough, and this causes the body cells to imbibe the fluids and swell, as per WebMD [7].

Make it a rule to drink just enough water throughout the day in small bits instead. Drink a few sips before your workout, especially if you're doing it in the morning.

Related Articles:

  • Should I Drink Water While Working Out?
  • What Not to Eat Before a Workout?

6. Drink Too Much Caffeine

Although there is evidence linking caffeine use to improved performance, there may also be severe adverse effects.

According to a study published by Medicine & Science in Sports & Exercise, caffeine use before or during exercise may raise the risk of blood clots [8].

During two high-intensity training sessions, the researchers monitored 48 men and discovered that caffeine boosted their coagulation factor.

The males who had caffeine-containing beverages before working out were more likely to get blood clots, associated with significant medical conditions like heart attack, stroke, deep vein thrombosis, and pulmonary embolism.

7. Over Moisturize Your Skin

A woman moisturizing her skin

Working out with excess moisturizer on your skin can clog sweat glands and skin pores, making it difficult for your skin to breathe.

I've seen cases where over-moisturizing before a workout led to discomfort and even safety issues. One of my female clients had a close call with weights slipping due to excess lotion.

If you have dry skin, try using light moisturizers in fewer amounts before working out. Otherwise, it would be best to avoid it altogether.

8. Take Anti-Inflammatory Medication

While it's tempting to pop over-the-counter pain meds for pre-workout aches, it's often not the best move. These drugs don't just target the pain area – they affect your whole body.

Moriarty Physical Therapy's research warns that painkillers pre-exercise can lead to more injuries, as they mask pain signals critical for avoiding overstrain [9]. 

Additionally, most medications relax muscles, which can negatively impact your muscles and reduce your performance.

According to WebMD, Ibuprofen may worsen exercise-related intestinal damage and impair the gut barrier in healthy gym goers and athletes [10].

Dr. Rainier Guiang cautions that nonsteroidal anti-inflammatory drugs (NSAID) before workouts could reduce organ blood flow, risking organ damage or heart attacks.

Instead of reaching for meds for minor aches, consider rest days to let your body recover naturally. For serious, ongoing pain, it's best to consult a doctor.

9. Finish Intense Sets Back to Back

A woman hurting her back from having intense back to back workouts

Research published in the National Library of Medicine reveals that back-to-back workouts without proper rest can lead to overtraining syndrome (OTS) [11].

Pushing too hard, especially with closely spaced sessions, can backfire, harming your health and stalling progress.

Studies in Frontiers confirm OTS can lower fitness levels, hurt performance, and increase injury risk [12].

This is true for intense routines like HIIT, aerobics, and weightlifting, which can lead to burnout. To avoid this, exercise within your limits and prioritize recovery time.

Remember, post-workout self-care is crucial to recharge and maintain your exercise momentum.

10. Consume Alcoholic Drinks

It only takes a little alcohol to impair your ability to manage your body.

Additionally, it damages your coordination and focus, making it difficult for you to do the sets in the proper form, and this affects your performance in the long haul.

It's best to skip your next workout if you're enjoying a happy hour with your friends that day.


Is It Okay to Nap Before a Workout?

Yes, it's okay to nap before a workout to get extra rest. Make sure you time your nap, so it doesn't interfere with your static stretches workout schedule.

Should You Poop Before The Gym?

You should poop before the gym if you have to. Emptying your bowels will keep you comfortable throughout your workout.

How Long Is a Power Nap?

A power nap is 10-20 minutes long.


  1. https://www.jsams.org/article/S1440-2440(18)30030-6/abstract
  2. https://link.springer.com/article/10.2165/00007256-200737120-00006
  3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4551211/
  4. https://www.hsph.harvard.edu/nutritionsource/carbohydrates/fiber/
  5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5257219/
  6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4027093/
  7. https://journals.lww.com/cjsportsmed/Fulltext/2015/07000/Preventing_Deaths_Due_to_Exercise_Associated.1.aspx
  8. https://www.webmd.com/diet/what-is-too-much-water-intakehttps://www.urmc.rochester.edu/childrens-hospital/allergy/exercise-induced-anaphylaxis-eia.aspx
  9. https://moriartypt.com/the-use-of-painkillers-is-widespread-in-sports-most-do-not-understand-the-consequences/
  10. https://www.webmd.com/sex/what-are-reproductive-rights?ved=
  11. https://pubmed.ncbi.nlm.nih.gov/35320774/
  12. https://www.frontiersin.org/articles/10.3389/fnetp.2021.794392/
Was this article helpful?

About The Author

James Cunningham, BSc, CPT
Staff Writer & Senior Coach
James Cunningham, BSc, CPT holds a BSc degree in Sport & Exercise Science from University of Hertfordshire. He's a Health & Performance Coach from London that brings a unique blend of academic knowledge of health supplements and practical exercise experience to the table for his readers.
Learn more about our editorial policy
Benedict Ang, CPT, PN1-NC
Staff Writer & Senior Coach
Benedict Ang, CPT, PN1-NC is an ex-National Soccer player turned MMA and Kickboxing champion, with ACE CPT and PN1-NC certifications. His advice is rooted in education and experience, ensuring that readers receive scientific and battle-tested insights. His mission is to empower his clients and readers to realize their potential and become the best versions of themselves.
Learn more about our editorial policy
Dr. Harshi Dhingra, MBBS, MD is a published peer-reviewed author and renowned physician from India with over a decade of experience. With her MBBS from Bharati Vidyapeeth and an MD from Rajiv Gandhi University, she actively ensures the accuracy of online dietary supplement and medical information by reviewing and fact-checking health publications.
Learn more about our editorial policy

You May Also Like

Clamshell Exercise Featured Image
By Lisa Lorraine Taylor, BSc, CPT 3 months ago
Clamshell Exercise: Why Should You Do It & How to?
A woman working out with a battle rope at the gym
By Benedict Ang, CPT, PN1-NC 1 month ago
15 Battle Ropes Benefits (& Why You Should Start Using Them)
A person at the gym doing dead hang workouts
By Connor Sellers 15 days ago
Dead Hang Benefits (And Why Should You Do It)
Do Eggs Increase Testosterone Featured Image
By Dr. Harshi Dhingra, MBBS, MD 3 months ago
Do Eggs Increase Testosterone? (4 Things You Need to Know)
A male runner suffering constipation in the middle of a race
By Dr. Harshi Dhingra, MBBS, MD 19 days ago
Do Steroids Cause Constipation? (7 Things You Should Know)
Close up shot of a sack of soy poured on a table
By James Cunningham, BSc, CPT 5 months ago
Does Soy Lower Testosterone? (4 Things You Need to Know)

Write a Reply or Comment

Your email address will not be published. Required fields are marked *

Our scoring system is the result of objective testing data and subjective expert analysis by a team of fitness coaches and medical experts. Our scoring factors are weighted based on importance. For more information, see our product review guidelines.