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Product test

Love at second sight - the "Forerunner 645 Music" from Garmin tested

Patrick Bardelli
16.5.2018
Translation: machine translated
Pictures: Thomas Kunz

It's time, time for a new relationship. That's why I'm on the lookout and in the testing phase, so to speak. Who buys a pig in a poke? Exactly. The Garmin "Forerunner 645 Music" is a wearable with 4 GB of music storage. My conclusion: it's love at second sight.

On the other hand, laziness is completely alien to me when it comes to jogging. I like to run a lot. My best half marathon time: 1:49:00. The Garmin Forerunner 645 Music predicts a marathon finish time of 3:50:00. What else does the sports watch achieve apart from this bold prediction? We'll see.

Week 1

Getting to know each other

Since I've been listening to my music via Spotify or Deezer for some time now, my iTunes library is pretty outdated. I had transferred the tracks from various CDs many years ago. These songs cannot now be transferred to the watch. The problem is that the tracks are DRM-protected and therefore cannot be converted into a compatible format (AAC, MP3). There is certainly some freeware on the Internet that can do this. But as I said .... see keyword: lazy sack.

Meet the family

The Forerunner 645 Music is equipped with advanced running efficiency functions. To utilise these functions, Garmin also offers the "HRM-Run" heart rate chest strap. I also tested the compatible "X3" Bluetooth headphones from Jaybird. Total cost for watch, strap and headphones: around CHF 750.

First impression

With its 42 millimetre diameter and silicone strap, the Forerunner 645 Music is an elegant piece. However, it has its price. In addition, I can't use my music from iTunes. I either buy new music or wait until my Deezer playlists can be synchronised with the Forerunner 645 Music. According to Garmin, this should be possible with the update at the end of June/beginning of July.

Conclusion of the first week

I miss the ex (Apple Watch Series 2). Our relationship hasn't been sparkling for a while now, the butterflies in my stomach have disappeared. But we simply have a solid foundation where everything is well-rehearsed and works smoothly.

Week 2

The first time

I'm a little nervous. That's often the case the first time. After all, I don't want to fail. That's why I proceed with caution and don't take the Forerunner 645 Music on a long, intensive run just yet. Today I'm going to the gym, without a chest strap for the time being. My usual workout consists of:

  • 10 minutes warm-up on the treadmill
  • 40 minutes workout on various machines
  • 20 minutes of cardio training on the treadmill

I wear the X3 from Jaybird in the "over the ear" version. This means the cable is close to the back of my head and doesn't get in the way during my workout. That's great, I don't even notice that I'm wearing headphones. The sound is good. However, I don't focus much on the sound quality, I'm training. My credo: if something doesn't attract negative attention, it's fine. And that's the case here.

After the workout, the watch provides me with valuable information:

  • Speed
  • Heart rate
  • Cadence
  • Training effect
  • Running efficiency

I think I did well. Because the watch is telling me that this activity involves intense aerobic effort at my lactate threshold and this workout is likely to improve my lactate threshold.

Of course, that's great to hear after a strenuous workout. If I were a smoker, I'd have a cig afterwards.

The second time

Today, the stakes are high. After the positive experience of the first time, I now want confirmation. I'm planning a longer run including the chest strap to utilise the advanced running efficiency functions. The X3 headphones from Jaybird are on board again. They are really comfortable to wear and work well. Only at the start of the run is the Bluetooth connection not very stable. This leads to these annoying little interruptions.

The Forerunner 645 Music and I are on the road for just over an hour and cover 12.5 kilometres in this time. Everything works perfectly, whether it's music or voice messages. That's why I'm curious to see what the analysis of the chest strap data will reveal. And these advanced functions for running efficiency are simply amazing.

With the chest strap, the Forerunner 645 Music also measures biomechanical values:

  • Vertical ratio:

This is the cost-benefit ratio between vertical movement and distance travelled.

  • Vertical movement:

Up-down movement during the run.

  • Balance of ground contact time:

Balance between left and right leg during the run.

  • Ground contact time:

High cadence + fast pace = shorter ground contact time.

And it provides information regarding:

  • VO2max:

This is the maximum oxygen uptake per minute per kilogramme of body weight at maximum performance. This value provides information about cardiovascular fitness (the condition of the cardiovascular system).

  • Performance status:

This value provides information about the general state of performance and the state of fatigue during a long running training session.

Wow, I'm thrilled. These are really cool features that will help me to analyse my runs better in the future. I can work more specifically on my running technique and improve my performance. The whole thing is easy to control via the "Garmin Connect" app, and after a little trial and error, it's also very clear.

Conclusion of the second week

I think I'm in love!

Week 3

Battery full, bottle empty

Garmin promises a battery life of up to seven days in smartwatch mode and twelve hours in GPS mode for the Forerunner 645 Music and keeps this promise. When playing music, the battery should last up to five hours in GPS mode. The goal for today is therefore: 21.1 kilometres (half marathon) in a maximum of 2:00:00. 50 per cent charge should therefore be enough for a good two-hour run with music.

After just a few hundred metres, I realise that today is not going to be my day. It's not my day and AC/DC isn't helping. I'm tired and my right foot hurts. So I torture myself over 12.6 kilometres in 1:12:00 and am glad when it's over. Running is sometimes hell. My energy level is close to zero, the battery of the Forerunner 645 Music is still charged to a good 50 per cent.

Everyone was in good shape today: the watch, the chest strap and the headphones. Except for me.

Other features

I deactivated the "Smart Notifications" function after a few days. It shows you all incoming messages. From email to WhatsApp to text messages. If you like to keep up to date and have a constantly buzzing wrist, leave this function active. It tends to get in the way during sport.

The watch is water-resistant to around 50 metres and, weighing just over 42 grams, is not even half as heavy as the "Fenix 5X Saphir" from Garmin (98 grams).

About weight

Rule of thumb: 1 kg extra weight per 10 km = 1 minute time loss

But back to the reality of the amateur runner. The watch has now accompanied me for three weeks during my sporting activities:

  • Jogging: 25 kilometres
  • Treadmill: 30 kilometres
  • Strength training: 5 hours

Conclusion

I have found a new love. In combination with the chest strap, the Forerunner 645 Music offers everything I expect from a sports watch as an amateur runner - and more. The advanced functions for running efficiency are great. The watch provides me with a large amount of data that I can work with in the future. The design impresses with its simple, sporty elegance.

I can also recommend the Bluetooth headphones from Jaybird. You can tell that they are made by athletes for athletes. In the "over the ear" version I chose, they are comfortable to wear and don't get in the way at all when running. The sound quality also suits me.

As soon as the Deezer update is added in the summer, I'll be completely happy. Or should I say, I would be completely happy? After testing it, I'll have to return my new love to our purchasing department. I'm not sure I can cope with that.

The entire Garmin range

The Forerunner 645 from Garmin is also available without the "Music" function:

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From radio journalist to product tester and storyteller, jogger to gravel bike novice and fitness enthusiast with barbells and dumbbells. I'm excited to see where the journey'll take me next.


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