Repeat Sprint Set — Long Rest (45s): A Complete Guide
Quick Intro
Repeat Sprint Set — Long Rest (45s) is a Speed & Agility exercise performed by running a series of short maximal sprints with 45 seconds of rest between each one, giving the body enough time to recover so every single rep can be run at top-end sprint quality. It is an easier version of Repeat Sprint Set, extending the rest interval beyond the standard roughly 30 seconds so less overall stress accumulates across the set, even though each individual sprint is still run at full effort.
Equipment Needed
No equipment is required. A flat running surface long enough for a 20 to 40 meter sprint and a stopwatch or interval timer to hold the 45-second rest steady from rep to rep are all this exercise needs.
Why Repeat Sprint Set — Long Rest (45s) Matters
Each sprint still drives hard through the glutes (gluteus maximus) and front of the thigh (quadriceps, rectus femoris) to extend the hip and knee, with the hip flexor (iliopsoas) whipping the leg forward into the next stride. The back of the thigh (hamstrings, biceps femoris) and its inner counterpart (hamstrings, semitendinosus) slow the swinging leg and drive it back into the ground on every stride, while the calf (gastrocnemius) and deeper calf muscle (soleus) supply push-off force at each ground contact. The shin (tibialis anterior) lifts the foot clear between strides, and the lower back (erector spinae) holds the trunk stable through a sprint run at full effort. Speed is the main demand, as high as in the standard version, since every rep in this longer-rest format is still meant to be run at the same top-end effort. Power and cardiovascular endurance both come with it, the cardiovascular demand lower than in the standard set, since spacing sprints further apart lets more of the aerobic and anaerobic recovery happen between reps rather than stacking on top of unfinished fatigue.
When to Do It
This fits near the end of a speed or conditioning session in the same way the standard set does, after sprint mechanics and acceleration work are already warmed up. It suits the same intermediate and advanced athletes the standard version suits, and it’s also a reasonable option for anyone returning from a recent hamstring or calf strain who wants to keep sprinting at full speed without piling on the same accumulated fatigue a shorter rest interval creates. Because every rep is still a maximal sprint, the same caution about form breaking down under fatigue still applies, even with the longer recovery window.
Getting Ready
Run through the same dynamic movement prep and progressive build-up strides as the standard set, working from roughly 50 up through 90 percent effort before the first full sprint. Set the rest timer to 45 seconds before starting and rehearse the exact start position that will be used for every rep, so the first stride out of the line stays consistent whether it’s rep one or rep ten.
Step-by-Step Instructions
- Mark the course and set the 45-second timer. Measure a straight 20 to 40 meter stretch and set the rest timer specifically to 45 seconds per rep.
- Settle at the line. Take up a two-point standing stance or a light three-point stance, whichever the base set uses, with the weight loaded forward.
- Sprint at full effort. Drive out and accelerate through the entire distance at maximal effort, using the full 45 seconds of rest as license to hold nothing back on any single rep.
- Walk back and use the extra time. Let the longer rest window bring the breathing fully back down before the next rep, rather than treating it as time to fill with extra movement.
- Begin the next rep once the timer hits 45 seconds. Start exactly on the clock, and compare each rep’s time or effort against the one before it to confirm the longer rest is holding quality steady.
How Many, How Often
Dosage here is set by rep count within a fixed 45-second rest, since the rest length itself is what sets this version apart.
| Level | Where you’re at | What to do |
|---|---|---|
| Beginner | New to repeated sprint work | 4-5 sprints of 20m with 45 seconds rest |
| Intermediate | Comfortable holding top speed across reps | 6-8 sprints of 20-30m with 45 seconds rest |
| Advanced | Training top-speed quality specifically | 8-10 sprints of 30m with 45 seconds rest, ending once times start slipping |
Holding identical sprint times across every rep matters more here than total rep count, since the generous rest exists specifically to make that consistency achievable.
Modifications and Variations
This exercise has one harder step: Repeat Sprint Set, which shortens the rest to roughly 30 seconds. Beyond that, Repeat Sprint Set — Short Rest (15s) cuts the rest again for anyone who wants fatigue to build across the set.
Common Mistakes to Avoid
Coasting through reps because the rest feels generous. A 45-second window is meant to protect sprint quality, not an invitation to hold back effort on any single rep, since every rep still needs to be run at maximal speed.
Cutting the rest window short because recovery already feels complete. Shortening the 45 seconds because breathing has settled collapses this version back toward the standard protocol’s stress level without gaining anything from doing so.
Adding extra reps simply because the rest makes it feel easy to keep going. The point of this version is holding sprint quality across a set number of reps, and tacking on more reps past that point turns a speed-quality session into a conditioning one by accident.
After Your Set
Reach into a standing hamstring stretch, one foot propped slightly ahead with the knee soft, hinging forward from the hips until a stretch is felt through the back of the thigh and its inner counterpart. Follow with a half-kneeling quad stretch, the back foot held up behind and the pelvis tucked underneath, to release the front of the thigh and hip flexor after repeated maximal drive.
Going Deeper
This exercise pairs naturally with single-effort acceleration work earlier in a session, the same as the standard set, since both build the raw sprint mechanics this protocol repeats. Progress here tends to stall in a specific way: because the rest feels generous, it’s easy to keep the rep count and distance exactly the same session after session without ever testing whether times can hold at a slightly longer distance or a slightly faster pace. The fix is nudging one variable at a time, distance or total reps, only once times have stayed flat at the current volume for several sessions. This version suits athletes building repeated-sprint capacity for the first time, along with anyone easing back into full-speed sprinting after time off or a minor strain, since the accumulated stress across a full set stays noticeably lower than the standard protocol’s.
How to Know You’re Improving
- Every rep in a set lands within a narrow, consistent range of your fastest time.
- Breathing returns close to normal well before the 45 seconds run out.
- Total reps completed at full quality climbs across sessions without times drifting apart.
- The set can shift toward a slightly shorter rest or a slightly longer distance while times hold steady.
The clearest sign of progress is a set where the slowest rep barely differs from the fastest one.
Muscles Worked
- Gluteus Maximus (the largest glute muscle, able to give peak output on every repetition)
- Rectus Femoris (a front thigh muscle that crosses both the hip and knee, cycling the leg at full rate on fresh legs each time)
- Biceps Femoris (a muscle at the back of the thigh, working at top speed with the rest it needs to stay safe)
- Gastrocnemius (a calf muscle, firing at a force level fatigue never gets to blunt)
- Iliopsoas (the deep hip flexor, driving a sharp knee lift on every rep of the set)
- Semitendinosus (the inner hamstring, recovering enough between efforts to handle top-speed loads)
- Soleus (a deeper calf muscle beneath the gastrocnemius, taking high but well-spaced impact doses)
- Tibialis Anterior (a muscle along the front of the shin, keeping a crisp ankle action on the last rep as on the first)
- Erector Spinae (the muscles running along the length of the spine, holding good posture throughout the session)
FAQ
Is this an easier workout than the standard Repeat Sprint Set? The overall session asks less of the recovery system, but each individual sprint is still run at full effort, matching the standard version’s top speed demand (see Why It Matters above).
Why use 45 seconds of rest here instead of the standard roughly 30? The extra recovery time protects sprint quality on every rep, which matters most for anyone whose times start dropping off too early under the standard rest length (see Quick Intro above).
Can I use this version if I’m coming back from a hamstring strain? It’s a reasonable option, since it keeps full sprint speed in the session while asking less of the body’s accumulated recovery demand than the standard set (see When to Do It above).
How do I know when to stop the set? The same rule as the standard version applies: stop once times start dropping off significantly, even with the longer rest window in place (see Common Mistakes to Avoid above).
Should I eventually move to the shorter 15-second rest version? Only once this version’s times are consistently solid and a specific training goal calls for adding more accumulated fatigue to the set (see Going Deeper above).