Speed Legs

What it's for

[Mountain Legs](https://runsense.ai/articles/mountain-legs.html) supports most runners across most training, but there's sometimes a gap for people doing very fast running — particularly around hamstring and glute strength. Speed Legs was built to close that gap. It's more targeted than Mountain Legs, and it's only worth adding if you have some evidence you need it — a weakness, an imbalance, or a health issue that shows up at higher speeds or on hard downhills. If nothing is bothering you, Mountain Legs alone is plenty.

Unlike Mountain Legs, Speed Legs tends to sap next-day energy even after your body adapts to it — so it rides best on a day followed by an easy run or a rest day, not right before a hard session.

The 5 exercises

Do these back to back, in order, resting as needed between sets. Start completely unweighted — the first time through can leave you sore for several days — then progress to a light dumbbell and eventually a kettlebell as the moves feel controlled and easy.

1. Alternating rear lunges — 10 per leg. Step back into a lunge, alternating legs each rep so you don't fatigue one side before the other.
2. Bulgarian split squats — 10 per leg. Trailing foot elevated on a bench or step, lower and rise under control. Skip or scale back if you have knee concerns.
3. Single-leg Romanian deadlifts — 10 per leg. Standing foot planted, hinge forward as the other leg extends back, then pull through the glute and hamstring to rise. Start unweighted — this one rewards patience.
4. Goblet squats — 10 to 20 reps. Feet shoulder-width or a little wider, squat to a comfortable depth holding a weight at your chest once you're ready to add load.
5. Single-leg step-ups — 20 to 50 reps per leg, finishing the routine. A step or box roughly knee height works well; drive up through the working leg without pushing off the trailing foot.

How often

Twice a week is typical, ideally on a day followed by an easy run or rest so the next-day fatigue doesn't compromise a harder session. Don't rush between exercises and don't push any set to failure — the goal is a real stimulus, not exhaustion. Ease in: unweighted for the first couple of weeks, then add a light dumbbell, then a kettlebell as the movements feel controlled.