Mike Boyle trains athletes on one leg, because that's how sport happens. Here's how to make single-leg strength the default.
Running, cutting and jumping are single-leg actions - yet most programs build lower-body strength on a bilateral back squat. Mike Boyle flips the emphasis: loaded single-leg strength becomes the primary lower-body method for field and court athletes, for better sport transfer, exposed left-right asymmetries and far less spinal load. This breakdown covers his case in our own words, adds our take for a client roster, and turns it into a single-leg template you can program.
By Markus Evers · September 2026 · a Coachway video breakdown
the short version
Boyle's case is that because sport is played mostly on one leg, loaded single-leg strength - split squats, single-leg deadlifts and the like - should be the primary lower-body method for multi-directional athletes, with the bilateral back squat deprioritized: it transfers better, exposes and fixes left-right asymmetries, and loads the legs hard while sparing the spine. The one thing a coach should do about it: for field and court athletes, make loaded single-leg work the main lower-body strength lift rather than an afterthought - and progress each leg on its own merits.
Mike Boyle - Unilateral Training Updated
Source: Mike Boyle Strength & Conditioning on YouTube - "Unilateral Training Updated". Watch on YouTube. We embed the public video and summarise it in our own words; the video, title and channel belong to Mike Boyle / Mike Boyle Strength & Conditioning, and nothing here implies their endorsement of Coachway.
Who is Mike Boyle, and why coaches watch
Mike Boyle is one of the most influential strength and conditioning coaches of the last few decades, known for training elite and team-sport athletes and for shaping how a generation of coaches thinks about functional, sport-transferable training. His gym, Mike Boyle Strength & Conditioning, is a well-known name in athletic development, and he's long been associated with the shift toward single-leg training in athlete programming. Coaches watch him for a practical, sport-first philosophy that asks a simple question of every exercise: does it transfer? This unilateral-training case is one of his signature positions, which is the lens this page is written for.
What Boyle actually argues (our summary)
This is our summary of the ideas in the video, in our own words - not a transcript. Watch the original for his exact framing and examples.
- 1
Sport is mostly single-leg. Running, cutting, decelerating and jumping happen off one leg - so train the pattern that actually transfers to the field.
- 2
Deprioritize the bilateral squat. A heavy back squat loads the spine and doesn't match the one-leg demand of multi-directional sport - it's supporting work, not the centrepiece.
- 3
Single-leg strength is the primary method. Loaded split squats, single-leg deadlifts and their progressions become the main lower-body lift for athletes.
- 4
It exposes and fixes asymmetries. Working one leg at a time reveals left-right differences a barbell hides - so you can find and close the gap.
- 5
Lower spinal cost. You can load the legs hard without the axial load of maximal bilateral squatting - useful for durability across a season.
Coachway's take
We're largely on board, especially for field and court athletes and for general clients whose backs don't love heavy bilateral squatting. Single-leg strength is under-programmed relative to how well it transfers, and it's joint-friendly enough to be a great default for a lot of people, not just athletes. Making it the primary lower-body method - rather than a token set of lunges at the end - is a genuine upgrade for most multi-directional athletes.
Where we'd add nuance: this is a shift in emphasis, not a rule that squatting is bad. Bilateral work still builds maximal strength and suits some athletes and goals, so the honest coaching version is "single-leg leads, bilateral supports" rather than "never squat". Match the emphasis to the sport, the training age and what the athlete actually tolerates and transfers from. And treat the back-sparing benefit as risk-reduction coaching, not a medical claim - a diagnosed back issue is a clinician's call, and you program within their guidance.
The under-appreciated payoff is the asymmetry information. Because each leg works on its own, single-leg training turns into an ongoing assessment: if one side lags in load or quality, you can see it and address it, where a barbell would let the strong side quietly compensate. For a coach, that per-side data is as valuable as the strength itself - it's how you catch a problem before it becomes an injury or a performance leak.
So our version of his approach is: for field and court athletes, make loaded single-leg strength the primary lower-body lift, progress each leg on its own merits, watch the per-side loads for asymmetry, and keep bilateral squatting as supporting work where it genuinely fits the athlete.
Program the progression, watch each side
Single-leg training only pays off if the progression is programmed and the per-side data is visible. In Coachway you build the single-leg ladder once in the workout builder - split squat to rear-foot-elevated to single-leg variations, loaded and progressed - so each athlete has a clear path rather than a random lunge. Then the load and reps per leg come back through check-ins, so a lagging side shows up as data you can act on instead of an asymmetry hiding under a barbell. The philosophy is Boyle's; the platform just keeps the progression and the per-side numbers together.
For the athletic-development picture around it, the companion breakdowns on Lee Taft on speed and agility and Eric Cressey on rotational power cover the movement and power sides of the same athlete.
The single-leg lower-body template (adapt per athlete)
A short template for building lower-body strength around single-leg work. The movements are examples - fit them to the athlete's level, equipment and any guidance from their clinician.
Single-leg lower-body template
| Slot | Movement | Why |
|---|---|---|
| Primary (knee) | Loaded split squat / rear-foot-elevated split squat | Main single-leg strength lift; sport transfer |
| Primary (hip) | Single-leg deadlift / 1-leg RDL variation | Posterior-chain strength, one leg at a time |
| Support | Bilateral squat/hinge where it fits the athlete | Max-strength base; supporting, not central |
| Progression | Own the pattern, then add load / complexity | Strength lift, not an afterthought finisher |
| Track | Load and reps per leg, each session | Surfaces asymmetry you can then address |
How to use it: make single-leg work the primary lower-body strength lift, progress each leg on its own merits, and log load per side so asymmetries surface. Keep bilateral squatting as support where it suits the athlete. Training guidance only - a diagnosed back or joint issue is a clinician's call, and you program within their guidance.
SINGLE-LEG LOWER-BODY TEMPLATE (via Coachway) - single-leg strength leads, bilateral supports; track each side - PRIMARY (KNEE) -> loaded split squat / rear-foot-elevated split squat | main single-leg strength lift; sport transfer - PRIMARY (HIP) -> single-leg deadlift / 1-leg RDL variation | posterior-chain strength, one leg at a time - SUPPORT -> bilateral squat/hinge where it fits the athlete | max-strength base; supporting, not central - PROGRESSION -> own the pattern, then add load / complexity | it is a strength lift, not an afterthought - TRACK -> load and reps PER LEG, each session | surfaces asymmetry you can then address HOW TO USE: For field/court athletes, make loaded single-leg work the PRIMARY lower-body strength lift and progress each leg on its own merits. Log load per side so left-right asymmetries surface. Keep bilateral squatting as SUPPORT where it suits the athlete - single-leg leads, bilateral supports. Training guidance only: a diagnosed back or joint issue is a clinician's call; program within their guidance.
Single-leg training for athletes - FAQ
Why train single-leg instead of the back squat for athletes?
Because sport mostly happens on one leg. Running, cutting, decelerating and jumping are largely single-leg actions, so loaded single-leg strength - rear-foot-elevated split squats, single-leg deadlifts, step-ups and the like - tends to transfer more directly to the field or court than a heavy bilateral squat. Single-leg work also loads the legs hard while sparing the spine of maximal axial load, and it exposes left-to-right differences a barbell across the back can hide. Boyle's argument isn't that squatting is bad; it's that for multi-directional athletes, single-leg strength earns the primary spot in the program.
Does this mean an athlete should never barbell squat?
No - it's a shift in emphasis, not a ban. Bilateral work still has a place for maximal strength and for clients who tolerate and benefit from it. The point is which pattern is the default: for field and court athletes, Boyle makes loaded single-leg strength the main lower-body method and lets bilateral squatting play a supporting role rather than the other way round. A coach picks the emphasis based on the athlete's sport, injury history and what they actually transfer from - single-leg leads for most multi-directional athletes, bilateral fills in where it fits.
How do you load and progress single-leg strength?
Treat it like any strength lift: pick a progression the athlete can own with good position, then add load and complexity over time. A common ladder runs from split squats and rear-foot-elevated split squats to single-leg squats and single-leg deadlift variations, loaded with dumbbells, a trap bar, a barbell or a landmine as control improves. Because it's single-leg, watch the quality per side and progress each side on its own merits, rather than letting the strong side carry a bar. Log the load per leg so the progression - and any asymmetry - is visible.
Is single-leg training actually safer for the back?
It generally lets you load the legs hard with far less spinal compression than maximal bilateral squatting, which is one reason coaches reach for it with athletes who don't tolerate heavy axial loading - so as risk-reduction coaching, it's a sensible default. That said, this is training guidance, not a medical claim: if an athlete has a diagnosed back issue or pain, that's a matter for their clinician, and the coach programs within whatever guidance the athlete has been given. Used well, single-leg work is a way to keep building lower-body strength while managing the load the spine sees.
More athletic-development breakdowns
- · Lee Taft on speed and agility - the movement side of the multi-directional athlete.
- · Eric Cressey on rotational power - power through hip-to-shoulder sequencing.
- · The full library: fitness creator coaching breakdowns.
Build the whole athlete
all guidesLee Taft on Coaching Speed and Agility (Coach Breakdown)
Lee Taft's speed and agility method, broken down for coaches: coach change-of-direction as a teachable skill - deceleration first, then plant and redirect mechanics - with reactive drills that transfer to the sport.
Read the guideEric Cressey on Rotational Power (Coach Breakdown)
Eric Cressey on why hip-to-shoulder separation - not raw strength alone - unlocks power for rotational-sport athletes, broken down for coaches with how to program the sequencing and ballistic work.
Read the guideStew Smith on Periodizing the Tactical Athlete (Coach Breakdown)
Stew Smith on periodizing the tactical or occupational athlete, broken down for coaches: phase from an aerobic-endurance base into a strength block, emphasising one quality at a time so a broad-capability client peaks for the demand.
Read the guideFree tools for this: Weekly Training Volume Calculator · Calorie Deficit Calculator · Macro Calculator
Make single-leg strength the default
Single-leg training pays off when the progression is programmed and each side is tracked. In Coachway you build the single-leg ladder in the workout builder and log load per leg in check-ins, so asymmetries surface as data you can act on. Start your 14-day free trial and coach lower-body strength that transfers to the field.
