Will Reta decrease running performance?

[u/Traditional-Yam6959]

Hi, I’m a 20F looking to lose about 5 kg using retatrutide. I’m a long-distance runner and have completed multiple marathons, so running is a big part of my life, but I’m aiming to lean out slightly.

I took my first injection about a week ago and have already noticed a drop in my running performance, especially a slower pace. From what I understand, this can happen due to factors like increased heart rate, reduced calorie intake, and lower glycogen stores.

My question is whether this is just temporary while I’m on the medication, or if it could have longer-term effects. Once I stop retatrutide after a few months, is it likely that my performance will return to baseline or even improve, or could this dip in performance carry over?

Would really appreciate hearing from anyone with experience or insight on this.

[u/AutoModerator]

Hey u/Traditional-Yam6959, thanks for posting in r/ResearchCompounds.

If you notice suspicious behavior or promotional activity, please report it to the mod team.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[u/Thee_PRIDE]

If you eat less and hydrate less, which people tend to do on any GLP-1, then your performance will naturally decrease. Reta in and of itself does not decrease performance but its intended effect typically results in drops in performance.

I didn't have much of a drop in my running performance (mind you I was only doing 2 mg a week) as I supplemented a stimulant and a nice karbolyn + electrolyte shake.

Edit: Speaking as a fellow runner, ex-track athlete.

[u/enamuossuo → u/Thee_PRIDE]

This!

[u/Traditional-Yam6959 → u/Thee_PRIDE]

Im also on 2mg a week and have been able to drinks as much as usual with extra electrolytes but less food ofc, but with extra protein and nutrients

[u/Ill-Nectarine-80 → u/Traditional-Yam6959]

Your athletic performance across all aerobic workloads will fall off a cliff when your glycogen reserves reach full depletion. This is why people optimising for success eat gels on the road in enormous amounts.

Any use of GLP-1s to drive a calorie deficit will diminish your overall glycogen reserves and indirectly impact your performance. First you will deplete all the rapid release glycogen in liver and as the depth of your deficit increases reserves will be drawn from your muscles and eventually you'll just run out. At this time, you can only burn fat which is much less efficient and creates a bottleneck that leads to the final cliff in performance. Reta especially does this because Glucagon receptors are always burning the liver glycogen.

[u/secret179 → u/Ill-Nectarine-80]

Then what will be soloution for slimming effect with no that?

[u/DJ_Cat_Dad → u/Thee_PRIDE]

By definition, the third component hitting the Glucagon Receptors, increases energy expenditure and.... energy expenditure probably has a good amount to do with cardio.... so ya prob taking a dose that is only activated as Trizepitide. It should definitely, and does definitely, impact performance.

[u/RoboJobot]

Yes, mainly because you’ll be struggling to fuel yourself enough and losing weight/strength/endurance at the same time because of this

[u/Successful_Sail_713]

Short term? Yes most likely. After you come of the opposite will likely happen tho

[u/v0idl0gic]

The heart rate increase on Reta is problematic for some endurance athletes. For that reason if I was you I would consider Tirzepatide instead. It too can increase heart rate, but it's much more mild and more transient. So I guess, why are you thinking Reta and not Tirzepatide?

[u/SarahKH88 → u/v0idl0gic]

Why does it raise heart rate?

[u/v0idl0gic → u/SarahKH88]

Reta had a glucagon agonist and the heart has glucagon receptors.

[u/Traditional-Yam6959 → u/v0idl0gic]

Because I can’t get hold of it in the country I live in, it’s quite strict here and haven’t found anyone with that trug here

[u/372xpg → u/Traditional-Yam6959]

Where are you that you gave no problem getting reta an experimental peptide but not tirzepatide an approved peptide?

What is wrong with you? You are a high performing long distance runner. You want to take a drug to lose more weight. You are 20 and run marathons?! You are the exact opposite person that should be using reta or any glp peptide.

What you have is a mental illness called body dysmorphia, perhaps anorexia. Your body is likely in its most efficient place and you are not having any issues with poor signalling and overeating. The only outcome you are going to have is poor performance and damage to your health.

[u/Dear-Response-7218]

Why even consider a glp1 if you’re distance running? They are meant for obesity, not a 5KG loss for all the reasons you mentioned. Reta hasn’t been studied enough to understand the long term effects.

[u/Traditional-Yam6959 → u/Dear-Response-7218]

Yea I know, but I’m struggling with overeating if I try a natural deficit, just thought it might help with decreasing the mental energy I have to put in it

[u/BenSimmonsFor3 → u/Traditional-Yam6959]

Start low. If you are spending too much mental energy not eating, then this drug will do wonders for you. Don’t let people gatekeep it. 

[u/Unhappy-Revenue-3903 → u/Traditional-Yam6959]

Tirzepatide may help more with the overeating, but it’s a dual agonist. Where Reta is a triple. I have used both. I do like Reta better. But I am not sure what happens when you stop.

[u/Tacoboutem]

The two side effects which may affect your performance is delayed gastric/bowel movements and a higher resting heart rate.

How much or if at all it would affect running I'm not too sure.

[u/Markdlea]

Reta is causing you to eat less. Like you said: reduced calories, lower glycogen. Reta has caused you to “hit the wall” before you even started running. You will feel better once you settle into fat burning as your main source of fuel.

[u/Ginsdell]

It’s a common complaint

[u/javierf720]

It raised my resting heart rate a good bit and has made some efforts harder for me. I know you said reta but checkout the zepbound athletes subreddit,it'll give you decent insight in glp impacts on athletic performance.

[u/secret179]

If you are already athlete in shape don't use that. IMO it's for people who were candidates for bariatric surgery due to obesity.

[u/jimbeam001]

I am an ultra runner and recently ran a half marathon and actually had to take a break at around kilometre 12 due to the fact that my stomach felt really full almost too full and this usually happens because long distance running leads to the blood going to your legs instead of being in the stomach so that it just difficult to process any food that you intake. Without the GLP one it normally is not that easy to intake much food but now I found it is even way harder and the stomach really shuts down. On the other hand, I have found that running in the morning on water only if you’re doing a keto diet that the GLP one is really helpful because you burn your fat as an energy use anyway.

[u/Traditional-Yam6959 → u/jimbeam001]

Yes but isn’t it dangerous to do keto on Reta because of the possibility of ketoacidosis…

[u/Thee_PRIDE → u/Traditional-Yam6959]

Don’t fucking do keto on Reta. Fat is incredibly slow in digestion and with Reta already slowing your stomach down extensively, you will be able to eat much less than you normally would considering Reta already and turn into a slug. Low carb is ridiculous for a runner.

[u/gigantor21260 → u/Thee_PRIDE]

ultra runner Zack Bitter would disagree with you...

https://zachbitter.com/zach-bitter-low-carb

You clearly have NO experience with this and simply like to repeat nonsense you've heard as if it were factual information.

[u/Thee_PRIDE → u/gigantor21260]

Yes, I'm a sprinter? Of course my experience with low carbs is not going to be optimal?

[u/gigantor21260 → u/Traditional-Yam6959]

I've been keto/carnivore on and off for many years. I wondered about this issue, so I searched and searched before starting Reta. I was only able to find 2 examples of ketoacidosis connected to Reta. Both people were practically starving themselves, and both were terribly dehydrated. So... I've been keto/carnivore for the last 6 months on Reta, and it is working great for me.

I do think that if you are eating carbs, and so using mainly carbs for fuel, then Reta WILL certainly affect your running performance. You will be under fueling in a general sense, and if you are meeting your (high) protein goals, you are almost certainly eating too few carbs to ensure enough energy for you higher intensity runs or longer runs.

I think you could mitigate some of this by eating your daily carb allotment before your runs. Even on zero carb my body is able to refill my glycogen stores, although of course it takes longer than it does when I'm eating carbs, so... this route may mean longer times between runs.

I think as long as your caloric deficit is reasonable, and you are keeping yourself fully hydrated (both water and plenty of electrolytes) then you can feel good about experimenting with this.