Building speed without injury

Listen to the same fragment at two tempos. The fast version isn't "something else": it is exactly the same movement as the slow one, just compressed.

Here is the key: if at 60 BPM the pick moves too much, the hand squeezes or a note comes late, at 120 BPM those flaws don't disappear; they multiply. What you repeat is what you learn. That is why, in the forge, cleanliness is the requirement for raising the tempo, never the other way round.

Your best judge: the recording

While you play, your brain is busy playing and hears what it wants to play. Record yourself on your phone, even with its built-in microphone, and listen the next day: you'll hear timing slips and string noise that went unnoticed live. Recording the same exercise once a week also gives you something very valuable: evidence of your progress.

The metronome ladder is a simple method for raising the tempo without losing cleanliness. Look at the graph: the tempo doesn't rise in a straight line but in a sawtooth.

1. Find your clean tempo: the highest one at which the exercise comes out clean four times in a row.
2. Go up 4 BPM. If it's clean twice in a row, go up again.
3. When it fails, drop 8 BPM and play it clean. That's the "tooth" of the saw.
4. After three or four climbs, end the session with a slow pass, well below your tempo, with full attention. That's the one that sticks best.
5. The next day, start a few BPM below yesterday's maximum, not at it.

The ladder improves things gradually. Speed bursts attack the problem from another side: you play a very short fragment faster than your comfortable tempo, land on a long note and rest. Because the fragment is brief, your hand can stay accurate, and your brain learns what the fast movement feels like.

The method has three phases:

• One-beat burst: four fast notes that land on the target note, on the strong beat. Silence. Repeat.
• Two-beat burst: eight notes and a landing.
• Join: the whole fragment. If it breaks at some point, go back to the short burst that ends right there.

The number one reason speed stalls, and the cause of a lot of discomfort, is unnecessary tension. A tense muscle is slow: it has to overcome its own opposing muscle before it can move. Run this check several times in each session:

• Shoulders: are they creeping up to your ears? Let them drop.
• Jaw and breathing: are you clenching your teeth or holding your breath? Breathe normally.
• Fretting thumb: is it squeezing the back of the neck? Ease off until the note almost dies, then add just enough for it to ring cleanly.
• Pick: are you crushing it? Hold it with the minimum pressure that keeps it from slipping.
• Forearm: does it feel hard? Stop, shake out your hands and come back slower.

How you organise practice matters as much as what you practise:

• Always warm up: five minutes of slow, wide exercises, no chasing speed. Cold hands and maximum speed are a bad combination.
• Short blocks: attention and accuracy drop as soon as fatigue arrives. Work in blocks of 20 to 30 minutes with a few minutes' break between them, and change exercise often.
• Interleave: alternate techniques (picking, legato, tapping…) instead of hammering one for an hour.
• Sleep: motor learning is consolidated to a large extent while you sleep. A little practice almost every day beats a weekly marathon.
• Rest days: one day a week without intense technique work doesn't set you back; it helps you absorb.

The guitar is a safe instrument, but intense, repetitive practice can cause overuse injuries: inflammation or irritation of tendons and nerves in the wrist, forearm, elbow or shoulder (such as tendinopathies or carpal tunnel syndrome). They almost always give warning first. Stop and rest if you notice:

• Pain during or after playing, especially if it's sharp or still there the next day.
• Tingling, numbness or loss of feeling in your fingers.
• Weakness, clumsiness or cramps you didn't have before.

There is also a less common condition that is important to know about: musician's focal dystonia. It is a neurological problem, usually painless, in which a finger stops obeying during one very specific gesture (for example, it curls on its own when playing a scale), while working normally in everyday life. It has been linked to long hours of repetitive, high-precision practice, although its causes are not fully understood. If you notice something like this persistently, don't try to fix it by practising more: see a neurologist, preferably one specialised in performing arts medicine.

The hands you play with today are the ones you'll play with in twenty years. Treat them like your finest instrument.