As I have said before, I enjoy night running. For a successful outing, you need a good quality head torch. I look for good light output (above 450 lumens), small size, lightweight, high comfort and battery longevity. I have been testing the Petzl Swift RL head torch for runners and walkers.

Features of Petzl Swift RL head torch
- Light output: Up to 900 lumens
- 2 x light beam modes: Standard (steady) and reactive
- Light beam brightness: Standard: 10, 200, 550 lumens; reactive: 100, 300 & 900 lumens.
- Button lock/unlock function
- Beam pattern: Flood or mixed
- Battery: 2350 mAh Lithium-Ion rechargeable
- Charging time: 6 hours
- 5-level battery gauge
- IPX4 weather-resistant
- Weight: 100g
- Colours: Blue, orange, black
- Cost: £96.99 from Ellis Brigham. See Petzl for stockist.
- But from Ellis Brigham.



On test: Petzl Swift RL head lamp
Petzl has long been a leader in lightweight, high-lumen head lamps. I reviewed the Petzl Actik Core a couple of years ago.
For some time, they have also sold head lamps with what is called “reactive lighting technology”. These are part of the performance collection as “Reactive” head lamps. The Nao and Nao+ were the first head torches I saw with this technology and a few friends have them. The Swift RL also includes a reactive light beam mode.
A reactive light beam describes how the head torch reacts to light. So if the torch sensor detects a lot of light in the area already, it reduces the beam output. The theory is that where you require less light you save on battery use.
According to the charts issued by Petzl, you can save considerably on battery use and if you are a long-distance runner or someone doing a multi-day race, battery life is important.
The reactive sensor also reacts to what you are looking at, whether a map close up or into the distance.
The Nao was hailed a game changer at the time because it can be “programmed” for light output and synced with a smartphone to see burn time left etc. Some people have told me they have found the programming a bit of a faff and simply stick to what the head torch is set with. (There was also a collection of Petzl Reactiks but these are no more.)
The Petzl Swift RL is claimed to be an improved and simplified – head torch. It includes three standard light beams output up to a maximum of 550 lumens and three “reactive” beams up to 900 lumens.
But to start with I struggled to work out what mode I was in. After asking my brand contact, I discovered the head torch turns on in the default Reactive mode. This is good to know but I would have liked to see information/basic instructions of how to use the head torch readily available on the website.
Also, I asked, what if I stop, for example for a pee, and turn off the torch? How long does it take for it to reset? I couldn’t find this info anywhere. Again, I asked the brand contact, and I was told that when you switch off the head torch it always defaults to the “reactive” mode when switched back on.
When in reactive mode, for each press of the single button on the top of the torch you get a brighter beam. There are three brightness levels: 100, 300 and 900 lumens.
To go into “standard” mode you need to hold down the button for longer. Then you press through three brightness beams. In reality, I found it easier to switch off the torch and then hold down the button for a longer duration to switch mode. The three standard beam outputs are: 10, 200 and 550 lumens.
You can use the “lock” button to keep a chosen beam set. When I tried to use the “lock” button I ended up accidentally pressing the wrong button and switching up the beams instead. I gave up trying to use it!
Even after using this torch a few tines, I still found myself unsure which mode I was in. I asked for more expert help from Petzl and I was told there was a simple way to know if you are in standard and reactive: “The easiest way to check you are in reactive when the lamp is on your head is to put a finger over the reactive sensor on the left. The beam will go to full brightness in reactive but won’t change at all in standard.”
I tried this and I still got confused. Perhaps I am a bit dim or perhaps I need to get more used to the differences but in the end I just switched the beam to standard and got on with my run. I should point out I have used the head torch more than 20 times and in different locations and situations.
But when you are mid-run and trying to work out the best beam for the conditions, the last thing you want to do is stop, faff about, faff about some more, swear, ask your friend and then finally get going again.

Now to the reactive beam itself. Well, it does seem like a great idea. The battery is only used to the extent that you require a beam. Except, I have found a few flaws.
If you are running with someone else wearing a head torch, the Swift reduces its beam. I guess it thinks that between the two of you there is enough light for you both to run. Except, this is not the case. I like my own full beam to light my way and I don’t want to have to rely on someone else’s beam.
I ended up on a number of occasions “sharing” the beams of the dimmed Swift RL and the lower lumen output of a friend’s head torch.
Trail running often sees people running side by side, behind each other and then apart. You move together, apart and behind each other all the time. Sadly, the light beam seemed quite slow to react to my needs. Once it dimmed, it felt like it never came back to full brightness again. I have been told by the brand that I must be mistaken but I tested this several times and I found that the 900 lumens brightness I was hoping didn’t always seem that bright.
The same thing happens if you are running behind someone who is wearing a reflective detail on their clothes or pack. The beam reacts to the brightness of the detail and dims. This is annoying.
Another odd thing happened on a chilly evening. My breath appeared to cause the beam to dim, or was it the mist? Anyway, something caused the light to dim, which was annoying at best and dangerous at worst. I don’t want to have a dimmer beam when it is cold and I am breathing out, or in mist/rain/snow.
Further advice from Petzl is that to extend burn time a bit further you can point the lamp at your feet slightly more than usual. The reactive technology dims the beam but then gives you the brightness if you look up a little. This does work well.
In truth, and from what I have discovered when discussing the reactive technology with others, I think the reactive beam is far better for solo running or when you are walking. The pace of walking means that if the beam dims it is not so much of an issue compared to running. When running I usually require a bright beam to show me the way ahead.
I read that the reactive beam change is instant but this was not always the case in my experience.
If you are running or walking on your own there are far fewer variables for the reactive technology to be influenced by. Even so, I found that the beam didn’t stay as bright as I would wish it to be to be able to see my way ahead. I am wondering if this is because of my myopia. I know I prefer a brighter beam and perhaps I require a brighter light to run by than the reactive beam offers me.
I can see that this is a good head torch for long distance runners for whom battery life is vital. For example, if you were only planning to use one head torch and battery on a longer run, then you will enjoy a longer battery life. However, I am usually out for a maximum of about two hours at night and that means I would prefer to have a brighter, steady beam rather than relying on the reactive mode.
And if you are worried about the torch running out of battery charge, you might want to take an extra battery with you rather than relying on the reactive technology to give you extended hours.
A positive point about the reactive technology includes a good reaction to lighting up things in the near-distance (such as a map) and then in the far distance. Also, when you are looking at someone else who is also wearing a head torch, the reactive beam dims so it doesn’t blind the other person.
I am told (by the brand representative) that I am very firmly in a minority of people who don’t rave about the Swift and the reactive beam, but there you go. I am simply stating my opinion and how I have found the head torch. I have tested many head torches over the past decade so I feel qualified to say what works and doesn’t work so well.
I was looking forward to a beam that was bright enough to run with for most of the time but I did not find this in the reactive mode. The beam brightness was too variable to be enjoyable and reliable.
Instead, I switched to the standard brightest beam of 550 lumens and found that to be adequate.
Note, too, that while the Nao had the option to swap the reachargeable battery for AAA batteries, the Swift does not. You need to buy a spare rechargeable battery if you plan to use the head torch for many hours.
The thought behind the Swift is that you have two headlamps in one, a light/bright “standard” headlamp or a light/bright/extended burn time reactive headlamp, but I don’t think I’ll use the reactive mode as much as I had hoped I would.
I will carry on testing the reactive part of the head torch and update if I find it any easier to use.
More Petzl Swift RL features
Other features include the five energy battery bar gauge. This is really helpful when charging the torch because you can see whether it is fully charged. It also helps to show you how much charge is left while you are out on a run or adventure.

I like the head band, too. The double “split” band at the back provides a much better system for keeping the head torch in place. The single band of other head torches causes the lamps to move about, up and down. The band is also padded and that helps with comfort. I like that the split rear fits around my ponytail, too.
The button for changing modes can be easily used while wearing gloves, which is another advantage of the Petzl Swift RL.

Also, when charging the head torch you do not need to open up the case, as I have to do with the Actik Core.
The Swfit is said to be “weather resistant”. This is not waterproof although I have taken the torch out in Scottish rain and it seems to remain operative.
Conclusion: I love the size, weight and 900 max lumens output of the Petzl Swift RL head torch. The split rear strap keeps the head torch stable and on my head.
The jury is out for me on the reactive beams. I found them to be a bit frustrating. The reactive beam reacted too much to other people’s beams and to my breath/mist/rain. I felt that the beam become too dim on too many occasions to be really useful.
I prefer the standard light beam outputs. The max standard lumens is 550 and this is actually fine for most night running situations. I could be greedy and ask for more lumens bit this would require a larger battery and that would make the lamp heavier.
Saying that, on standard 550 lumens, the maximum battery time is only two hours. You will need to carry a spare battery if you plan to be out for longer. But when in reactive beam mode the battery use is far less.
This is not a cheap head torch and I think I’d rather have less technology and a lighter price tag. A possible alternative could be the Petzl IKO Core.
Also read: Petzl head torch for kids.
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