Week 7 fatigue, what's going on?

[u/inevitable_zest]

So as the title says, I've just finished week 7. But the last few runs I've really struggled more than before. I was finding running 20 minutes absolutely fine, my breathing was good and my legs weren't tired at all. I even went off the plan abit and built up to 25 mins gradually over a few weeks and felt great.

But now I start fine, then get to about 50-60% through the run and suddenly feel very fatigued. And my legs feel very tired. I'm not going any faster than I have been previously, in fact my pace is slightly slower. I still mange to finish the runs though. I even took a week off last week but it didn't seem to help.

What could be going on? I don't really understand why I'm suddenly struggling.

[u/arcadianbonerpart]

Keep going. I finished c25k 2 weeks ago. Every run was the punish. I just ran the 2nd run in w2 of 5-10K and had so much left in the tank.

Keep pushing, you’ll be fine.

[u/inevitable_zest → u/arcadianbonerpart]

Thanks for the encouragement :) sometimes hard to.stay motivated!

[u/arcadianbonerpart → u/inevitable_zest]

Sure is. I’m in Australia so the days are hot as fuck. Running at 8pm after I’ve put a kid to sleep is not ideal, but the feeling after finishing 30 mins of running makes it worth it

[u/Ok-Terrific2000]

How are you feeling all around? This is a busy time of year, are you stressed? Or it could be anything like hydration, nutrition, hormones, change in weather/season.

Assuming those are all your normal, maybe go back to a level that is challenging but comfortable for a couple weeks then look to push harder again and see how you go.

[u/inevitable_zest → u/Ok-Terrific2000]

Thanks for the advice! I might try easing off slightly. I'm not particularly stressed. Honestly it could be sleep/hydration/nutrition thing.

[u/ladyshapes]

Are you eating and resting enough?

[u/inevitable_zest → u/ladyshapes]

My sleep has been a little inconsistent of late. I was thinking it could be a sleep or diet issue. But honestly don't know what I'm supposed to be eating to help my running.

[u/ladyshapes → u/inevitable_zest]

A bad night's sleep really ruins my day and noticeably affects my physical performance :c

At this stage I think how much you eat (ie getting enough calories) matters more than what you eat. Good luck!

[u/Another_Random_Chap]

Hydration, nutrition, pace. If any one or more of those is wrong then you will experience what you're talking about.
Also consider sleep, stress & general health.

[u/undulatedcalm]

I had the same issues during my W7. Being able to run 25-28 mins is one thing, being able to run it consecutively can sometimes be too much for a beginner still getting used to the increased activity levels. Plus I feel the accumulated fatigue of having done the first couple of weeks caught up with me. I added some extra rest days and redid d1 and d3 of Week 7 before I was comfortable enough to move up to W8.

Rest is good. Depending on your diet, you may need to increase your calories a bit. Many people who pick up running and do the program are also actively trying to lose weight and going on a bit of a deficit like I was. In my latter weeks, I had to eat a bit more to keep up my energy levels.

[u/AbundantHare]

I just finished W7D2 and it was really hard. I left a day between W7D1 and W7D2. I found the first run to be fairly easy and enjoyable - I could talk all the way through etc - but yesterday’s run was difficult. I was definitely struggling.

I did it in a hotel gym that was very hot, I only had six hours of sleep the night before and we had been travelling internationally with a time change. My average HR went from 122 on D1 of W7 to 135 on D2.

For me it’s a combination of eating poorly (unaccustomed diet at Xmas), plus the sleep, plus travel, plus the gym being so hot and also leaving just one day between the runs.

I am leaving the rest of the week before doing D3 and hopefully that will make a difference.

Good luck!

[u/Pedal_up_hill]

It’s frustrating to hit a wall like this after making good progress, but it’s not uncommon. Here are some factors to consider and potential solutions to help you overcome this plateau:

1. Cumulative Fatigue

Even if you’ve taken a week off, your body could still be feeling the effects of consistent training. Sometimes, the build-up of mileage and effort over weeks can catch up to you.

Solution:

Consider incorporating a proper “deload” week every few weeks, where you cut back both the duration and intensity of your runs.

Add more rest or recovery days between runs if you’re feeling persistently fatigued.

1. Nutrition and Hydration

Running longer and consistently increases your energy demands. If you’re not eating enough or not balancing your diet properly, it can affect your performance. Similarly, dehydration can sneak up on you and cause fatigue.

Solution:

Make sure you’re eating enough carbohydrates, as they are your body’s primary fuel for running.

Stay hydrated throughout the day and consider adding electrolytes if you sweat a lot.

Have a small snack with carbs and a bit of protein (like a banana with peanut butter) about 1-2 hours before your run.

1. Sleep and Recovery

Sleep is when your body repairs and strengthens itself. Poor sleep quality or quantity can lead to tiredness and underperformance.

Solution:

Aim for 7-9 hours of quality sleep per night.

Ensure your rest days are true rest days with minimal activity.

1. Running Form or Overuse Injuries

Subtle issues in your running form or small niggles in your muscles can lead to inefficient movement and fatigue over time.

Solution:

Pay attention to your form. Are you running upright, with relaxed shoulders and good posture?

Stretch and foam roll after runs to alleviate tightness, especially in your calves, hamstrings, and quads.

If the fatigue persists, consider visiting a physiotherapist or running coach for a gait analysis.

1. Mental Fatigue

As you run longer and push your boundaries, mental fatigue can set in. This can make you feel like you’re struggling more, even if physically you’re capable.

Solution:

Break the run into smaller segments in your mind (e.g., focus on completing 5-minute chunks).

Switch up your route or listen to new music or podcasts to keep things interesting.

Practice mindfulness or meditation to help manage mental fatigue.

1. Iron or Other Deficiencies

Sudden and persistent fatigue during exercise could indicate an underlying deficiency, such as low iron levels or vitamin D.

Solution:

If your fatigue doesn’t improve, consider getting a blood test to check for deficiencies.

If needed, supplement under the guidance of a healthcare professional.

1. Overtraining or Burnout

Sometimes, even with rest, pushing too hard for too long can lead to burnout. Your body may need more time to recover than just one week.

Solution:

Take a step back and reduce the intensity and duration of your runs for a couple of weeks.

Cross-train with lower-impact activities like swimming, cycling, or yoga to maintain fitness while reducing strain on your legs.

Key Takeaway

Listen to your body. It’s great that you’re able to finish the runs despite the struggle, but pushing through fatigue consistently without addressing the underlying issue can lead to injury or burnout. Start with these adjustments and be patient as your body adapts. If things don’t improve after a few weeks, it might be worth consulting a coach or healthcare professional.

[u/Cold_in_Oz]

Struggling during a run does happen. Progress is not linear, many factors come into play, but overall keep at it and you will see it in a few months when you look at the big picture.

[u/Misty-Anne]

I can't remember how long it takes, but your activity level might have outstripped the rate your body was making blood cells. Your body will adapt, but it can't ramp up cell production immediately so it might take a bit.