Baselayer question: How tight is too tight?

Here's a link to the product in question:

http://www.ems.com/product/index.jsp?productId=21831386

I thought tight clothing helps increase circulation (thinking of those compression tights that diabetics have to wear).

I'm not expert but the tight clothing helps stabilize muscles and push blood back up and keep it from "pooling" in the extremities… yes no? i'm not sure.

I can say from personal experience that sleeping in compression tights can mean cool/cold from the waist down due to decreased circulation. Hiking in them has been fine but not sleeping. With the lightweight tights in question mentioned be the OP, I don't think it would be as noticeable as a pair of dedicated compression tights.

I agree. Tight base layers can lead to getting cold. They are fine when hiking, not too great for sleeping.

"I thought tight clothing helps increase circulation (thinking of those compression tights that diabetics have to wear). "

That help fluids LEAVE the area, so greater net circulation away from the extremities. Unfortunately, less blood flow from the warmer body core = colder extremities. Also added pressure means contracted capillaries and colder skin. On the other hand by the same principle, wearing tighter sleep socks may lower some swelling of the feet during the night. But they would have the potential to make your feet colder too.

My wife has swollen ankles. She wears compression socks sometimes to keep fluid from pooling. But the compression is very tight. Hard to get on. I don't think your base layers are enough to do that. Can you barely get them on?

Blood flow to the extremeties is under high pressure so is largely unaffected.

I tested some compression socks for backpackgeartest.org. I didn't notice them being warmer or colder or more or less comfortable. I was really trying to determine whether they were different.

If a baselayer is loose, there's a trapped air layer that can provide extra warmth, and more air circulation to keep cool if it's hot. Maybe these effects are negligible.

If a baselayer is just barely big enough, there will be less area of fabric so it will weigh a little less.

Compression socks also increases venous pressure, which is low. But I agree that the air gaps are as likely to effect your warmth if you aren't at the point where your toes are tingling because the material is so tight.. Insulation doesn't increase your warmth by its magical innate qualities, but by the way it traps air. I would assume for a lot of materials that it if it thigh as a drum on you body hen as Jerry mentioned, this would be minimized.

> Is it bad to have baselayers too tight? Will it reduce circulation?
Yes to both questions.

The current marketing craze over compression things like Skinz is driven entirely by marketing. There is ZERO truth in any of their claims, which manage to slide by the FDA. The so-called 'endorsements' from athletes are simply paid commercials and valueless. Fraudulent stuff.

The only research ever done was one study which found that compression tights might assist people with badly damaged valves in the veins in their legs. Other studies which have been done found negative effects for everyone else.

Yes, I have tested compression clothing, and yes, they did restrict my circulation, and yes, they did make me colder than I was later when I took them off.

Mind you, 'snug' fitting thermal baselayers which simply fit close to your skin rather than either squeezing or flapping – they are nice and warm.

Cheers
PS: we have already had one run-in with a rep from a vendor over my comments – but he went away after I challenged him to produce any published supporting medical research.

Having some considerable issues with circulation and the related problem of keeping warm under what most would consider mild conditions I would have to agree with those on the not so good idea side of the fence as far as really tight fitting bases. Of course my case would not be normal but restriction, even to a lesser degree will cause me to chill in those areas.

Fitted of course does not necessarily mean they will be constrictive, maybe just more form fitting to what you are used to. I like bases with looser fitting wrists and pant cuffs. Something that is not tight elastic. But again my needs are different. As with just about any piece of kit you just gotta give it a go.

jimmyb

Like others have said, yes, too tight will restrict blood circulation. Even if they are only a little tight, I wouldn't sleep in them.

I assume you are going to sleep in them?

I've personally experienced, that any clothing just remotely restricting when sleeping, has a negative effect on keeping warm. I always choose supersoft baselayers now.

Here is your physiology lesson for the day:

When people's extremities swell (heat, exertion, dependent positions (hands or feet hanging down), poor fluid management d/t heart failure or high blood pressure, or when you have varicose veins…) that means there is an imbalance in a pressure gradient in the tissues and that allows fluid to escape.

Our bodies function based on those pressure gradients, and at all times our bodies try to maintain a equal pressures across membranes. That means when pressure of something is higher than the pressure of something else on the other side of a barrier, the substances will cross the membrane however they can to equalize the pressure gradient.

This imbalance can be physical (i.e. high blood pressure (pathological or exertional): pressure in the vascular system > pressure in the interstitial tissues = fluid leaking out of blood vessels into the surrounding tissue until that pressure gradient is equalized.

The imbalance can be metabolic (i.e. imbalance of proteins in the blood vs the tissue), gaseous (this is how your cells are oxygenated), etc etc.

So when a diabetic, or someone with edema in the legs/feet, or lymphedema in the arm, etc wears compression garments, it's to try to balance that pressure gradient to prevent the fluid from escaping the vascular system (increase the pressure in the interstitial tissues, thus balancing the pressure gradient between the tissue and the blood vessel).

I have never understood why athletes would ever want to wear compression garments – perhaps to reduce superficial blood flow to force more blood into deeper tissues (muscles)????? Either way, after a quick search this morning I couldn't find any bit of literature to back up the claim that wearing compression garments during exertional activities would improve performance in any way.

That will be all for today.

A very significant way compression garments can increase performance, is simply by the wearer believing that they do perform better with them. A very significant part of high performance has nothing to do with any physiology, its mental.

But also, compression garments can reduce unwanted movement of muscle groups in between contractions, ie flopping around. Possibly making them less tired and sore.

NM

> compression garments can reduce unwanted movement of muscle groups in between
> contractions, ie flopping around. Possibly making them less tired and sore.
Sorry, but if you can believe in muscles 'flopping around' then I have a bridge you might like to buy.

Cheers

I was thinking the same thing, Roger.

Muscles don't "flop around" and burn more energy.

By you asking this question it already says to me you feel a little uncomfortable. In that case it's too tight…would be for me as I like comfortable clothes. I have however cycled and trained heavily for state and national events here in Australia in the past and can say even when my coach directed me to wear compression tights for 'recovery' (sleep in overnight) I HATED it. I couldn't imagine having that much restriction.

Weather or not what does compression tights offer when hiking or relaxing I think that is not the way you want to head if you are asking the original question.

"Sorry, but if you can believe in muscles 'flopping around' then I have a bridge you might like to buy."

Me, too. Maybe we could give him a two for the price of one?

Do they come in "snake oil" yellow? They might help.

Experience example free of physiological reasonings – though I appreciate Jennifer's very clear post, helpful to a lay guy interested in these things. I find that base layers are warmer when they fit well but not tight. Not sure if this is because the cold/damp get through more easily when they are very tight across your skin, or that a little room for air to warm and remain (assuming an outer layer blocking wind. In any case I am a borderline between small and medium tops. Some brands "S"; some brands "M". The most comfortable and best performing have always been the larger – and slightly looser – cuts. I suppose this could be a coincidence due to brands or materials, but I am doubtful. There is also a MIke McClelland tip on this in one of his pack dump videos. He is talking about shirts but suggest the base layer over your t-shirt (his method) should be slightly loose and not tight. The usual disclaimers, of course, apply here, so add the appropriate acronyms in all caps as desired.

Using the famous colloquial, "if you have to ask…" it's probably too tight.

In all seriousness though, as others have done a good job of explaining, it's a balance between comfort, increased circulation (as a function of decreased retention), and decreased warmth (as a same function). Mostly comes down to personal preference.

As someone who spends an equal amount of time in cold weather as warm, I find that the very best warmth performance comes from garments that fit as snugly as possible but are not tight. They should merely rest against your skin.

The reason for this is two-fold. Where there are air gaps that can change size with movement, etc, causes a pump effect, moving warm/cool air around instead of simply containing a comfortable, consistent microclimate.

Second, if and when you do sweat, the dampness is wicked away much more efficiently with fabrics in constant contact with your skin. It also pushes moisture out more effectively by your body heat, and you don't get the immediate chills of cooled fabric touching your skin.

In warm weather the latter is more important. You can quickly become uncomfortable when the dampest parts of your base layers cool off from being away from your skin and then touch you again. You will cool off just fine with the base layer in constant contact with your skin, but you won't feel as sticky and damp as a baggy base layer.

As others have mentioned, a layer that actively compresses your body is counterproductive by restricting blood flow at the surface of the skin.