If you have shopped for a light for running or walking at night and compared headlamps, flashlights, Knuckle Lights and even other options, you have likely seen a lot of reference to “Lumens.”  And those lumen numbers can be all over the board.  So what does it really mean and which light will actually work best during your activity?

In essence, a lumen is a measure of the intensity or brightness of the light source, at the highest setting and powered by new or fully charged batteries.  Light output can range from a mere 20 lumens to a scorching 3000 lumens.  Theoretically, the higher the lumen rating, the brighter the light should be.  But while this number is a great starting point for comparison purposes, it does not tell the whole story about how the light illuminates the area in front of you and, thus, the effectiveness for night running or walking. 

If you have ever compared different headlamps or flashlights with similar lumen outputs, you may have noticed they do not produce the same discernible amount of light.  Two lights might state they are 200 lumens, and while they may indeed be, the actual amount of usable light may be much different.

That’s because the Beam Type can be just as important in the actual effectiveness of the light to your particular activity.  The lens reflector that surrounds the LED bulb influences how the light is dispersed.  There are a few beam types, the more common being a Spot Beam, which is a single condensed beam of light that penetrates a long distance.  Many headlamps and flashlights are spot beams—when aimed at the ground you see a circular spot of light and not much illumination around it. 

The other type is Flood Beams, which emit light in all directions, and therefore illuminates your entire path immediately in front of you.  Since there is no condensed beam of light, this type of beam does not pierce through the darkness like a spotlight, so the distance of actual illumination is less.

So how do you determine the best light for your next run or walk in the dark?  Spot beam lights may have high lumens, but not work as well for night running and walking because you only get a relatively small area of light at a point in front of you, compromising your immediate surroundings.  Flood beams are better suited for these activities, as your entire path is illuminated; however, the sacrifice will be in distance the light illuminates, as the flood beams will not reach as far as a spot beam.

One other important consideration is if the light is rechargeable or battery operated.  Typically, battery operated lights will have lower lumen output levels in order to preserve and extend the life of the batteries, so that you are not constantly needing to change them.  Rechargeable lights can emit higher lumens but will likely have a much shorter burn time before needing to be recharged, which is usually a very easy process compared to changing batteries.

Knuckle Lights were designed specifically for running and walking in the dark, so while the lumen output level is similar to comparably priced headlamps, the units have wide flood beams in order to clearly illuminate the entire area in front of you, assuring you can clearly see any trip hazard.

Hope that helps clarify a bit about lumens.  Ideally, when choosing a light for your particular activity it may be beneficial to look at pictures or videos, either from the manufacturer or actual users (Instagram is a great source), that show the light output from the user’s view or perspective.  That should give you a good idea of how the light will illuminate the area in front of you to see if it fits your needs.