Why Am I Suddenly Struggling to Run?

Table of Contents

Why Am I Suddenly Struggling to Run?

Table of Contents

As the sun rises, you lace up your running shoes and begin your morning jog. You love this time of day—the fresh air, the chirping birds, and the feeling of freedom as you pound the path beneath your feet.

However, this past week has been tough. For some reason, you can’t run as far as you’re used to. Your muscles feel sluggish, your breathing labored. Despite your best efforts, your body is simply not cooperating.

Yes, a sudden decrease in endurance or a general feeling of fatigue can be frustrating. So, we’re here to help you explore the potential reasons behind the sudden drop in running pace. And we’ll discuss how the naturally occurring dipeptide called carnosine can get you back on track

Let’s get started! 

7 Reasons Why You’re Suddenly Struggling to Run

1. Poor Training Habits

Poor training habits include:

  • Increasing the speed or intensity of your training too soon
  • Not giving your body adequate time to rest and recuperate between and after workouts 

In fact, if you exert yourself too much, you could start to suffer from a condition called OTS (Over Training Syndrome) or burnout. At first, you may feel muscle soreness that’s more intense than unusual. And if you continue to push through and train without resting, you will begin to experience overtraining syndrome

Symptoms of OTS include:

  • Fatigue and a lack of energy
  • A suppressed immune system with regular chest infections
  • Changes in appetite
  • Impaired athletic performance. 

To prevent the effects of overtraining, take a few weeks off from running and ensure your body is in peak physical condition before tackling your usual training regime.  

2. Weight Gain

Another reason why you could be suddenly struggling to run is weight gain. The reason for this is that when you pick up weight (fat mass), it can have several repercussions on your body.  

For example, your heart, oxygen consumption, body temperature, energy expenditure and pressure on your joints and bones will increase, leading to less energy and stamina when running. Reducing fat mass will reduce your body’s need for oxygen, and this, in turn, reduces your energy expenditure.  

Therefore, if you have gained a considerable amount of weight, you can expect some difficulties with running. You will also typically notice a sudden decrease in your cardiovascular fitness level. However, take note of whatever difficulties you may be facing and adapt your training routine and goals to better suit your current physical condition. 

For example, you might want to focus on a 2-mile run initially and slowly increase your endurance with time. Realistic goals will help you keep a positive mindset, push you to improve and not give up.  

3. Not Getting Enough Quality Sleep

Lack of sleep affects your overall energy levels, making it harder to find the drive and endurance to run. You might also feel emotionally and physically worn out, making running seem like a chore.

Ask yourself, are you getting sufficient sleep? Although most of us aren’t, we cannot stress the importance of sleep enough.

Sleep deprivation substantially impacts your capacity to function, especially as a runner. Lack of sleep also prevents your body and mind from having enough time to rest and recuperate, which has several detrimental effects on your running performance.

Running on little to no sleep increases your risk of injury and illness. Sleep deprivation limits your coordination – Meaning that you might be more prone to sprains or a twisted ankle. If you want to perform at your best, you need ample sleep. According to the CDC, this means 7 or more hours of sleep a night for adults between the ages of 18 – 60.

4. Not Warming Up

Without a proper warm-up, the body is ill-prepared for the physical demands of running, leading to a difficult and challenging experience.

Warm-ups help increase blood flow to the muscles, raise body temperature, and activate the cardiovascular system, which is essential for efficient oxygen delivery during exercise. Skipping this crucial step can result in stiff muscles, decreased range of motion, and a higher risk of injury.

Additionally, without a warm-up, the body may take longer to reach its optimal performance level, leaving the runner feeling sluggish and tired throughout the session. By making the warm-up a priority, runners can set the stage for a more enjoyable and productive running experience, with reduced discomfort and an overall better performance.

5. Poor Mental Focus

Sometimes, it’s our minds that buckle rather than our legs. You’ve most likely heard other runners discuss these difficulties. Or you may have listened to and seen them give up after a week or two of training. 

However, the more you train, the more your body (including your brain) adjusts, just as with any other physical activity. As a runner, mental tiredness can be one of the primary sources of your running difficulties. In particular, focus on half marathons (13.1 miles) and longer. 

Some other tips that you could use to stay mentally focused during your runs are:

  • Have a mantra and talk positively to yourself 
  • Have a moving target, and once you reach it, praise yourself and move on to the next finish line.
  • According to Runnersworld, runners who smile use less oxygen and therefore run more economically. So even if you aren’t feeling it – fake it till you make it. It might be just what you need to improve your running.

6. Low Hydration

Drinking enough water is essential, especially when running. Some runners might only drink water when they feel thirsty after a run, and in certain situations, they may only drink a little water during shorter periods of activity or long runs.

However, rehydrating can take up to 72 hours after a long run or a race. Therefore, maintain a healthy hydration level throughout the day and during your workout. As a result, you will recover more quickly, and your running efficiency will enhance.

7. Injuries 

Injuries come in all shapes and sizes. Your body will have less energy to fuel your running as it must focus on healing. Even if an injury is not in an area of the body used for running—though, let’s admit it, running uses most of the body—it can still impact your ability to run.

While light exercise can increase blood flow and speed the healing of wounds, it must be done carefully and under control. Ensure that you’re giving your body enough time to relax and recover. And if you need to, think about changing your routine.

I’ve Taken Time To Rest and Recover – Now What?

We know how impossibly difficult it is for a runner not to run. So, if you’ve managed to be disciplined and take time to recover – well done!

So what’s next?

Consider turning to a natural supplement that will shorten muscle recovery time and get you back into your running shoes much sooner.

How Carnosine Will Help You Perform At Optimal Levels For Longer 

Although there are many different supplements and vitamins on the market today for runners, we’d like to focus here specifically on carnosine.


Because carnosine has proven to be highly effective in aiding both performance and recovery in athletes. 

Carnosine plays a crucial role in buffering lactic acid produced during intense physical activity. By buffering lactic acid, carnosine helps delay the onset of muscle fatigue, allowing individuals to sustain high-intensity activities for longer periods.

It is a naturally occurring dipeptide, composed of the amino acids beta-alanine and histidine, found abundantly in skeletal muscle tissue. This intriguing supplement has been the subject of much research, including this study by Front Physiol

The purpose of the study was to investigate the effects of β-alanine supplementation on a 10 km running time trial and lactate concentration in physically active adults. The results?

The time to complete a 10-km running time trial decreased significantly and presented lower blood lactate concentration.

By increasing the carnosine levels in muscles, athletes and fitness enthusiasts experience:

  • Enhanced exercise performance and capacity
  • Delayed onset of muscle fatigue
  • improved tendon, ligament and joint health
  • Reduced muscle soreness and recovery time
  • A host of other benefits, including improved immune function and protection against heart disease

Although carnosine levels can be increased by eating foods like turkey, chicken, green beans and white mushrooms or by taking it in tablet form, the most effective way is to apply it directly to the muscle group using a carnosine gel

The effect will be much stronger, and you’re more likely to get the desired result – a powerful, rewarding running session.

Final Thoughts

Experiencing sudden difficulties while running can be frustrating, but addressing the underlying factors and making necessary adjustments is essential.

What makes Carnosine so appealing is that it’s a natural supplement that our bodies already produce in small doses. This means a sports gel like Carnosport isn’t introducing a foreign product into your system. It’s simply supplementing and enhancing what your body already knows it needs to perform optimally.


[1] https://pubmed.ncbi.nlm.nih.gov/12696983/

[2] https://pubmed.ncbi.nlm.nih.gov/35914388/

[3] https://pubmed.ncbi.nlm.nih.gov/25494389/