Why do you get tired when you run?

[jsmoke]

Take a 5k, probably short for most runners.

After about 2.5k I feel a hit coming on, my legs get a bit sore and breathing increases, I'm also sweating a lot.

Why is this, is it a lack of oxygen getting to the muscles, is it dehydration from sweating, or lactic acid built up, of maybe it's carbon dioxide build up, or what is the process that's tiring you and making you gasp for air.

I assume if your muscles got a constant supply of oxygen then you'd be able to run for 1000's of miles.

 

[dave28]

your body uses up easily available energy first so you feel good for a while, your body cant keep feeding the muscles enough energy though and fatigue sets in

im totally knackard after 1 mile, i prefer cycling

 

[Reuben klang]

Do you regularly run or eat/drink healthily?

Slow down when you feel it coming tough but keep going. Maybe you’re just pushing it too hard.

 

[Rroff]

Won't link to it due to language but watch "The SCIENCE! - Could you become a Mirror's Edge runner IRL?" unfortunately some swearing (6:16 onwards).

 

[Lmg80]

Mind over matter, keep pushing stop looking at distance covered at regular intervals helps

 

[Blackjack Davy]

Take a 5k, probably short for most runners.

After about 2.5k I feel a hit coming on, my legs get a bit sore and breathing increases, I'm also sweating a lot.

Why is this, is it a lack of oxygen getting to the muscles, is it dehydration from sweating, or lactic acid built up, of maybe it's carbon dioxide build up, or what is the process that's tiring you and making you gasp for air.

I assume if your muscles got a constant supply of oxygen then you'd be able to run for 1000's of miles.

Build up of lactic acid switch over from aerobic to anaerobic respiration etc. Everyone gets it distance runners have stamina to keep going sprinters are almost entirely aerobic. Basically surplus oxygen gets used up so lactic acid builds up until you rest when the body has a chance to metabolise it then you get your energy back. Stamina builds up with training.

 

[muttclugg]

Mind over matter, keep pushing stop looking at distance covered at regular intervals helps

Interesting you say this. I went out this morning and I’ve got a new phone so Strava wasn’t set up properly and I was running without it calling out my km times. I enjoyed it but I was slow but I felt like I could have gone for miles. It’s made me rethink my approach so I’m going to spend some time covering distances rather than going for a quicker time. I was surprised how much that one change to my run changed my whole outlook on running.

 

[jsmoke]

Build up of lactic acid switch over from aerobic to anaerobic respiration etc. Everyone gets it distance runners have stamina to keep going sprinters are almost entirely aerobic. Basically surplus oxygen gets used up so lactic acid builds up until you rest when the body has a chance to metabolise it then you get your energy back. Stamina builds up with training.

so basically the body doesn’t manage oxygen very well if you get tired easily. Hence people turn to PED’s.

 

[SPG]

Simply 80% of infrequent runners run to fast, you can't push for a PB on every run.

Google 80/20 running.

 

[Lyla77]

Simply 80% of infrequent runners run to fast, you can't push for a PB on every run.

Google 80/20 running.

Wish I saw this article a few months back! Would have saved me my eventual injury I suspect.
Too much too soon is a killer. You think you are flying and that each run must be faster than the last. Then either fatigue or injury catches up.

 

[siezar]

I love long distance running. When I was younger I used to run at about 90% effort but that's really only good for short distances, the trick is to go at conversation pace ie you should be able to hold a conversation with somenone if they were running alongside you. Up until 4 years ago I thought that running a marathon, even a half marathon, was beyond my capabilities; however, now I run one marathon each year.

The best advice I can give you is to have a look at some you tube videos on running technique. When I first started out I had bother with my knees locking up in the middle of the night after I'd been on a long run that day(which was only 4 miles or so at that point) but after changing my technique I've done countless miles without any bother.

Also, what keeps me going(and I can't be the only one this happens to) is every time I want to stop from muscle ache or whatever I press on and 5 mins later I get a buzz from the sense of achievement from not giving up. This happens every 20-30 mins or so. When I get that buzz I get a boost of adrenaline that makes me think for a short time that I can go on forever!

 

[Deleted member 651465]

Interesting you say this. I went out this morning and I’ve got a new phone so Strava wasn’t set up properly and I was running without it calling out my km times. I enjoyed it but I was slow but I felt like I could have gone for miles. It’s made me rethink my approach so I’m going to spend some time covering distances rather than going for a quicker time. I was surprised how much that one change to my run changed my whole outlook on running.

I’d echo this.

For me personally, I can blast out sub 7-min miles and end up with a drained tank in 6 miles or coast at 8:30/9 min miles for what feels like forever. Longest was 14 miles at that pace.

I will add that I stopped using the interval segments years ago for the same reason. If it’s a route you know then it simply isn’t required (by that I mean you know when you’ve done 3 miles judging on past experience) and if it’s a new route then it can be soul destroying thinking you’re further on than you actually are!

I experimented with the Nike/Apple coaching runs where they have a coach that chimes in at 1, 3, 5 miles etc and found it ok but if you’re going long you really don’t want some bloke saying “you’re going great, start to pickup the pace now” when you feel comfortable.

My advice would be to do lots of short runs (4 times a week for 6 weeks) until you build up a decent level of stamina. Then add on a mile here and there depending on how you feel.

A running partner can help initially too, but don’t be afraid to go alone. By that I mean, I trained with the mrs for years and had a mental block about my pace because her stride length was much shorter than mine. I was tired after each run and used to see other people’s runs on Strava etc and be astonished at their pace… until I ran on my own and realised that I was conditioned to take shorter, faster strides (high cadence).

Try going somewhere that allows you to take a variety of routes back to your start, like a park etc. Do a short run of 2 miles and see how you feel.

Next time go slower and see if that helps. Once you find a comfortable pace stick with that until the stamina builds up. In a nutshell, pace should be the last thing to tackle.

 

[SPG]

Cheap heart rate monitor and watch. (Wrist based HRM are useless for excerise no matter what the apple fanboys will tell you)

Work out your max hearrate 220- Age

Then work out 80% of that or use online calculator to give you your zones, stay in zone 2. This will mean walking often. Stick with it for 6months and you will no longer be walking unless its a really steep hill. When i say walk its walk with purpose till your HR drops to Z1 then start running again.

 

[EdwardTeach]

Take a 5k, probably short for most runners.

After about 2.5k I feel a hit coming on, my legs get a bit sore and breathing increases, I'm also sweating a lot.

Why is this, is it a lack of oxygen getting to the muscles, is it dehydration from sweating, or lactic acid built up, of maybe it's carbon dioxide build up, or what is the process that's tiring you and making you gasp for air.

I assume if your muscles got a constant supply of oxygen then you'd be able to run for 1000's of miles.

Have you tried running further then 5k?

I always feel a bit rough at the beginning of a run, but normally will feel more comfortable a few k more. I will happily run 10k without prior training. When I did used to run regularly (10k, 3times a week) I always found the beginning few ks the worst.


I think the difficulty in the first couple of k, is kind like your body is being shocked, you're lungs, heart, legs etc are suddenly working much harder than they had been. It takes a while for the endorphins to kick in.

 

[jsmoke]

Have you tried running further then 5k?

I always feel a bit rough at the beginning of a run, but normally will feel more comfortable a few k more. I will happily run 10k without prior training. When I did used to run regularly (10k, 3times a week) I always found the beginning few ks the worst.


I think the difficulty in the first couple of k, is kind like your body is being shocked, you're lungs, heart, legs etc are suddenly working much harder than they had been. It takes a while for the endorphins to kick in.

Just did 6km. The difference is night and day now. I was just really unfit and mentally weak. I credit a lot to doing squats, they really changed everything for me. Now running at 5.30min/km feels like jogging yet stepping up to the next level is going to take a whole lot of pain again, which I'll do.

I'd really done nothing for over 15 years and was still living in the past like 25 years ago thinking I'm still a runner but in a month I've come right back to some sort of base fitness Some very painful runs though. So much is mental, my bodies been screaming to stop yet I made it. I truly realised today the power of the mind today, once its expects a set of variables it doesn't want to step outside of that framework. Feels good to be getting back.

 

[Deleted member 651465]

Have you tried running further then 5k?

I always feel a bit rough at the beginning of a run, but normally will feel more comfortable a few k more. I will happily run 10k without prior training. When I did used to run regularly (10k, 3times a week) I always found the beginning few ks the worst.


I think the difficulty in the first couple of k, is kind like your body is being shocked, you're lungs, heart, legs etc are suddenly working much harder than they had been. It takes a while for the endorphins to kick in.

Really? I find the first few miles are always the easiest, mentally speaking.

If anything, my legs feel stiff for the first mile and it can take me about half that to hit a comfortable rhythm but if I know I'm going on a long run I can often zone out for the first half quite easily. I find that for me personally, I dread the final half mile as my mind is concentrating on the finish and I just want to "end", if that makes sense?

I try to vary this up by changing routes as much as possible so that I'm not actively thinking "this is going to take me another 4 mins, yawn". I often see it in my segment times on Strava too... I can be consistently within 2/3 seconds per mile for 4 or 5 miles and it' always the last 0.7 where my pace picks up