[DaveB]

I’ve recently been prescribed the beta-blocker propanalol for anxiety and hypertension (to supplement an SSRI I’ve also been taking). I’m 39 y/o, and despite a relatively solid level of fitness, blood pressure was typically 140+/90+ and I’ve had a very hard time relaxing lately and have not been able to get what feels like restful sleep (HRV apps often called for rest days after several days completely off).

I’m on a very low dose of propanalol (5 mg/day; standard dose is 40-120 mg/day), but one of the main things I’ve noticed since starting the script is that I feel like I’m recovering from training sessions much more quickly – which makes sense. While my resting HR has remained steady, chest strap HRV has improved and my Garmin “stress score” has improved as well (I understand this metric from optical sensors is mostly unreliable, but do think it can represent trends over time relatively well).

So, given the overall beneficial experience so far, I’m curious about what potential broader impacts there may be of blocking adrenaline production on endurance training? Or is it that I was just in a state of excessive adrenaline?

There’s not much in the literature about using beta-blockers with athletes or in younger fit-ish individuals. It seems that promoting rest-and-digest parasympathetic states is all benefit, but it also seems doctors tend to prescribe beta-blockers more as a last resort when treating hypertension. I can’t find a clear indication of why.

Apologies for the somewhat nebulous question, I’d also be very interested to hear any others’ experiences with beta-blockers as well.

Topic

[Anonymous]

Anonymous on January 29, 2020 at 3:06 pm #37079

First, don’t use HRV apps. Their recommendations are often way off.

The only thing I know about beta-blockers is that many are PEDs.

As far as other effects, I would track down a sports medicine specialist.

[Hav]

Hav on February 4, 2020 at 10:53 pm #37485

No first hand experience, but I do work as a clinical pharmacist at a hospital.
5mg is about the lowest dose prescribed to adults. These doses are not intended to treat hypertension, and are usually taken as needed for anxiety (ie taken immediately prior to giving a presentation).
Taking a low dose of the immediate release formulation should minimize/avoid the potential side effects for athletes since the effects are dose dependent and the duration of effect will be shorter (6+ hrs).
At higher doses (80mg+ daily) of the long acting formulation, propranolol would be antagonistic to endurance training: reducing max HR and inhibiting the ability to elevate HR during exercise, as well as reducing the strength of the heart’s contractions. These are the reasons BBs are effective at treating hypertension (although there are better medications with fewer side effects for that). BBs main medical benefit is in reducing the oxygen demand of cardiac muscle and stress on the heart in patients with cardiac disease. Additionally, BBs can also cause issues in people with Asthma, making it difficult for the smooth muscle of the lungs to relax.
At higher doses, metrics for recovery like resting HR would become suspect. I’d say if you are experiencing less stress overall and sleeping better and most importantly feel recovered, you probably are recovering better. The drug is not accelerating any recovery processes.
I would avoid taking the propranolol prior to exercise. If you have to take it before, I’d try and wait 6 hours before exercising and take note of how you feel with and without taking a dose beforehand so you can properly space it out.
Propranolol is considered a PED in some sports due to it’s ability to calm nerves and shaky hands. Beneficial in sports requiring fine motor movements under pressure, but detrimental in endurance sports (I’m sure it’s be trialed in the biathalon).
As far as long term effects of Beta blockers on athletic developement, I’m sure that depends on the dose but I’m not aware of any studies.
Hope, that helps.