“Any music used during indoor cycling will reduce perceived exertion by 8 per cent, even if it’s just arbitrarily selected: if you’re listening to the radio in the background, for example.

“If the music is well selected with the individual’s musical taste, personality traits and the specifics of the session in mind, the benefit can be as great as 12 per cent.”

So says Costas Karageorghis – professor in sport and exercise psychology at Brunel University of London – who over three decades has established an international reputation for his research into the psychological, psychophysiological and neurophysiological effects of music.

“However,” he adds, “there’s one very important caveat. Although music is highly effective at reducing perceived exertion at low to moderate intensities of exercise, it has virtually no effect at high intensities.”

Perceived exertion

“Cycling is particularly effective in helping us understand how music takes effect during exercise,” Karageorghis continues. “Its simplicity allows us to control a broad range of factors and reduce experimental error.”

Over the last decade, he and his team have conducted a series of studies simultaneously examining the electrical activities of the brain and muscle function, with a number of fascinating discoveries.

“At low to moderate intensities of cycling, music blocks fatigue-related signals from entering focal awareness,” he says. “This is possibly one of the key mechanisms to help us understand why we get an 8–12 per cent reduction in perceived exertion when we play music during low to moderate intensities of cycling.”

For those interested in the why: “Music reduces the capacity of the afferent nervous system, which takes messages from the working muscles to the central processor. If you think of the afferent nervous system as being analogous to internet bandwidth, music takes up some of that capacity, leaving less bandwidth for fatigue-related signals to enter focal awareness.”

Music can’t influence what we feel during high-intensity cycling, but it can influence how we feel it

He continues: “Then there’s something our group has explored very recently, which is how different clusters of neurons in the brain fire in response to music during exercise. We found that music reorganises our brain activity. We need less conscious processing to cycle with music than we do without music. This reorganisation of brain activity relates directly to flow state – to being ‘in the zone’ during a workout.”

Other studies have explored how different regions of the brain communicate with one another. “We found that communication across somatosensory areas of the brain [the areas responsible for communicating fatigue] is reduced under the influence of music,” says Karageorghis. In layman’s terms: “Music reduces our exercise consciousness.”

Happiness   

In other non-cycling exercise-based research, Karageorghis and his team found music can “very effectively” tap the sensory areas of the brain that are responsible for regulating our emotions.

“As previously noted, music doesn’t reduce perceived exertion at high intensities. However, even at high intensities, music does seem to permeate the emotional regions of the brain.

“During high-intensity exercise, you might report a score of seven or eight on the 11-point RPE [Rating of Perceived Exertion] scale. But responding to a Feeling Scale, with music you might report +1 – you’re feeling ‘fairly good’. Without music, you might report -1 – you’re feeling ‘fairly bad’.

“So, music can’t influence what we feel during high-intensity cycling, but it can influence how we feel it. It can colour our interpretation of fatigue-related symptoms.”

Performance   

Returning to the topic of neurons firing in the brain in response to music, Karageorghis explains: “We found this was also associated with simultaneous firing of the vastus lateralis – the key working muscle in indoor cycling.” In less scientific terms: “We’re able to engage the musculature more effectively under the influence of music.”

When cycling at moderate intensities, the use of music makes us about 6% more energy-efficient

He adds: “We’ve also assessed efficiency during cycling, with and without music, and found that when cycling at moderate intensities, the use of music makes us about 6 per cent more energy-efficient.

“Music dissolves some of the inefficiencies in the movement chain and reduces oxygen uptake, which is an index of energy efficiency: the more we reduce our oxygen uptake, the more we’re able to achieve the same workload but with lower energy expenditure.

“Note that this is for recreational athletes only; the benefits are negligible for elite athletes. The music must also be used synchronously [pedalling to the beat] for a metronomic effect. It doesn’t work when music is played asynchronously [in the background].”

This improved efficiency has a “direct impact” on performance, says Karageorghis: “In a range of bipedal activities, music can engender an ergogenic [work-enhancing] effect in the region of 10–15 per cent in recreational exercisers.”

Five ways to use music

So, how can indoor cycling instructors use this information when creating playlists?

“Even before we get there, we should acknowledge the different ways in which music can be used,” says Karageorghis.

“We can use music before cycling as a stimulant or sedative, either priming the individual for the workout or helping them overcome their anxiety. So many people are self-conscious about going into an indoor cycling class. Music can help alleviate this – particularly songs with self-affirming lyrics.

During recovery, the brain is more malleable to external manipulation. This is where music takes effect.

“During cycling, music can be used asynchronously – a background stimulus to generally reduce perceived exertion and help people feel better – or synchronously, which can be active or passive.

“Active synchronisation is when you try to coordinate the RPM [revolutions per minute] of the pedals with the BPM [beats per minute] of the music. It’s a conscious process to tap the rhythmical qualities of the music.

“Meanwhile, passive synchronisation uses technology to facilitate music that follows your work. It requires no conscious effort.

“Then we have post-task music, with recuperative music the simplest to understand: you work people to exhaustion, then use music – generally descending from 90 BPM to 60 BPM – to bring them back towards their regular resting state.

“Finally we have respite music, which is something I’ve focused on recently in response to the abundance of HIIT-style classes. Respite music is used during recovery phases in between high-intensity bouts.”

If using music asynchronously, there’s a tempo sweet spot of 120–140 BPM for the full range of exercise intensities

Making exercise enjoyable

Continuing on the topic of respite music, Karageorghis explains: “You can have respite-passive music for static recovery or respite-active music for movement-based recovery – and our recent work shows respite-active music to be very effective both in assuaging negative feelings after bouts of high-intensity and in preparing people for the next bout.

“During very high-intensity bouts of exercise, the messages that travel through the afferent nervous system are so strong, so overwhelming, that they render music a relatively ineffectual stimulus. But during recovery, physiological systems immediately decline and the brain is more malleable to external manipulation. This is where music takes effect and allows you to mentally prepare participants for the next bout of work.”

All of which brings us to exercise hedonics and the peak-end rule, which states that: “It is how people feel during the peak intensity of any activity and how they feel at the end that they carry into future activities of a similar nature.” In other words, the peak and end moments are crucial to how an exercise experience is remembered.

“The fitness industry hasn’t cracked this at all,” Karageorghis observes. “The focus has always been on personal goals, appearance and shifting kilos rather than immersing people in the actual process of exercising and rendering exercise palatable – even enjoyable.”

In bipedal activities, it’s a lot easier to have a whole revolution to a beat rather than a semi-revolution

Through his recent focus on respite and recovery, Karageorghis is showing the industry how to do things differently, evidencing “the power of music to make the belly of the workout pleasurable and help people leave class feeling positive” – and potentially more inclined to engage on a long-term basis.

The perfect playlist

So how does all this come together in the perfect indoor cycling playlist?

“To begin with, we must acknowledge that it’s complex and that one person’s music is another person’s noise. Instructors must also actively decide whether to use music asynchronously or synchronously.

“If you’re using music synchronously, you’ll need to do a lot of preparation to ensure BPMs align with the desired RPMs. One useful tip based on the work we’ve done: in bipedal activities, it’s a lot easier to have a whole revolution to a beat rather than a semi-revolution. It requires much less brain processing and makes the whole thing easier for your participants. I’m not sure how many instructors know that.”

He continues: “If you’re using music asynchronously, we’ve modelled the relationship between exercise intensity and preference for music tempo. This body of work, now spanning four studies, shows a tempo sweet spot between 120 and 140 BPM for the full range of exercise intensities.

“Higher than that and the music is almost overwhelming: it provides too much stimulation, requires too much processing and does not optimise psychological or psychophysical outcomes.”

And what about respite-active music? “Slow music doesn’t work well, downregulating activation to such a degree that you’re not prepared for the next bout of work, while high-intensity music leaves you feeling over-aroused. Music between about 120 and 125 BPM seems to work really well.”

During high-intensity exercise, the damage from ear-level music beyond about 85 decibels can be permanent

Karageorghis also points to the role of extramusical association and lyrical content – that is, selecting songs with a relevance to cycling. “These factors aren’t as potent in predicting the motivational qualities of music as the rhythm, harmony and melody, but they can be the icing on the cake,” he explains.

A final warning

He concludes with two words of warning. The first: “Cycling and music are a marriage made in heaven, but only when cycling indoors. Music is such an intoxicating stimulus that it can easily lead the outdoor cyclist towards danger.”

The second is of crucial importance to the entire fitness sector, whether you’re an instructor or a participant: “The cochlea – part of your inner ear – is surrounded by thousands of follicles. During high-intensity exercise, blood flows away from the cochlea to the working muscles, leaving the follicles susceptible to damage from music beyond about 85 decibels at ear level. With repeated exposure, the damage can be permanent, leading to conditions such as tinnitus.

“This is an important message, since it’s not unusual to go into a cycling class with ear-level music between 95 and 105 decibels. A safe level would be 75 decibels.

“Multiple smaller speakers around a studio, rather than two big ones blasting out the music, can be a good solution – otherwise wear earplugs.”

Applying the science

“As fitness director at Johnson Digital Studios and in my previous role as head of group exercise at Third Space, I’ve curated music around the scientific principles Costas has talked about,” enthuses Antony Stewart.

“Historically, that has meant manually managing the tempo, rhythm, structure and intensity to tick all the boxes, but I’ve always wanted to automate the process.” The result is the BeatFit app.

When it’s a song participants don’t recognise, the emphasis is on rhythm, intensity, tempo and structure

Designed initially with the asynchronous, time-protocol application of music in mind, BeatFit launched in 2024 complete with a small library of copyright-cleared music across all genres. Suitable for all modalities of training, indoor cycling is well within its remit; the team is currently curating and writing the music for digital in-app versions of David Lloyd’s Cyclone and Rhythm programmes.

“Indoor cycling has been synchronous for a long time, but increasingly we’re seeing clubs and studios introducing time- and power-based protocols that use asynchronous music,” says Stewart.

“In this scenario, instructors first create the workout, then tell BeatFit what they need. They might have eight rounds of 30 seconds’ work / 90 seconds’ recovery and want a priming track at the beginning and a recovery track at the end; they can specify the tracks’ duration. BeatFit then stitches together a bespoke playlist that perfectly matches the required intensities throughout.

“It also works for synchronous music, helping ensure the songs in a rhythm cycling class are exactly the right length and tempo and feature the proper work/recovery ratios.”

He adds: “To Costas’ point about one person’s music being another person’s noise, we’ve seen neutral music elicit a better average rating than well-known music. BeatFit learns your preferences when you reject songs and we’re looking closely at lyrics and associations, but when it’s a song participants don’t recognise, the emphasis is on rhythm, intensity, tempo and structure. You don’t have to worry about it being a song some people will love but others will hate.”

Stewart concludes: “We’re applying this thinking in all our virtual fitness content creation at Johnson Digital, too, with curated music and colourful graphics on screens behind the instructors that match the music intensities. It really adds to the overall exercise experience.”