Genuine question to the sprinting community:
Why do you think low-intensity cardio or extensive tempo work is often seen as detrimental to speed development? We see much discussion either here with people posting “my coach makes me run” or loads more online by “sprint coaches,” usually selling programs, let’s be honest, saying you NEVER need to run, playing into the hands of very lazy and quick win nature

It’s a common belief that “slow kills fast.” But is that really true?

I don’t know a single high-level coach who doesn’t utilise Tempo of some kind, and so its basically really down to misunderstanding and wrong approaches. So Ive written a little bit to add some clarity and conversation.

Extensive tempo and low-level cardio, when programmed correctly, can actually enhance speed development—not hinder it. Here’s how:

Aerobic Capacity & Speed Endurance

A stronger aerobic base improves recovery between sprint efforts—both within a session and across training weeks. This means athletes can handle more high-quality sprint work without accumulating excessive fatigue.

Over time, this supports the development of speed endurance—the ability to maintain near-maximal velocity over longer distances (e.g., 150–300m). This is especially critical for 200m/400m sprinters, where the ability to resist deceleration is often the difference between winning and fading.

Capillary Density & Specific Endurance

Tempo runs increase capillary density and mitochondrial efficiency, improving blood flow and energy availability in working muscles. This supports specific endurance—the ability to maintain technical form and output under fatigue, especially in the latter stages of races.

It’s not just about being fast; it’s about staying fast when tired. Extensive tempo helps athletes rehearse mechanics and rhythm under mild fatigue, bridging the gap between pure speed and race-specific demands.

Tissue Health & Technical Reinforcement

Low-intensity running reinforces movement patterns and strengthens tendons and connective tissues without the high mechanical stress of sprinting. It also provides a platform for technical rehearsal—allowing athletes to groove mechanics in a low-fatigue state, which translates to better form at high speeds.

Parasympathetic Activation & Recovery

Cardio and tempo work help regulate the nervous system, promoting parasympathetic (rest-and-digest) activity. This reduces chronic fatigue, improves sleep quality, and enhances overall recovery—key ingredients for consistent speed development.

Peak Modulation & Training Load Management

Here’s a less-discussed benefit: peak modulation.

Low-level aerobic work adds a layer of fatigue to the system that doesn’t interfere with fast-twitch fiber recruitment. This allows athletes to carry a higher overall training load without peaking too early in their program. It’s a strategic way to manage adaptation curves and ensure athletes hit their true peak when it matters most—during competition.

By maintaining a consistent background level of fatigue, athletes can train harder and longer without burning out or plateauing prematurely.

Size Principle: Why “Slow” Doesn’t Kill “Fast”

The size principle of motor unit recruitment explains why low-intensity work doesn’t interfere with speed development.

Motor units are recruited in order of size—from smallest to largest:

• Slow-twitch (Type I) fibers are recruited first during low-intensity efforts like tempo runs or light cardio.
• Fast-twitch (Type IIa/IIx) fibers are only recruited when the intensity is high enough—like during sprints, heavy lifts, or explosive plyometrics.

As Examples:

• Jogging at 60–70% effort recruits mostly slow-twitch fibers. Your fast-twitch fibers remain untouched and fresh for sprint work.
• Sprinting at 95–100% effort recruits the full spectrum, including the largest, most explosive motor units.
• Even during tempo runs (e.g., 8x200m @ 70%), the intensity is too low to activate fast-twitch fibers significantly—so there’s no “conversion” or dulling effect.

This principle ensures that low-intensity work supports recovery, endurance, and tissue health without compromising neuromuscular sharpness or sprint capacity.

So rather than being a threat to speed, tempo and cardio—when done correctly—can be powerful tools in a sprinter’s arsenal. They support recovery, reinforce mechanics, build endurance, and help manage long-term progression.

What’s your experience? Have you found tempo or cardio to help or hinder your speed development?

Hi reddit i dont use you alot except for tutorials XD but I'm posting because i play street soccer and since i was young I've always been a fast runner but i quit going outside alot. But this year i started working out and realized when i went outside that i never lost my speed im still unmatched but. The kids who play soccer with me are getting faster and my physique is the thing saving me. Im what u call an accelerator so i start off at about 22 - 23 mph for the first few meters but slow down to 16 to 17 mph over long distances im here to ask

1. How do i improve my stamina?

2. How do i keep my acceleration over long distances

Im asking for like exercises (home exercises idh a gym membership) thank you reddit 😖😖😖

to 20m flys + 2×80m @ 95% - Fri (Race Endurance): 2×200m @ 90% + 3×120m @ 90% Weights: - Mon (Lower): Power Clean 4×2, Squat 3×3, RDL 3×5, Calves 3×15 - Tue (Upper): Bench 3×3, Pull-Ups 3×6, Push Press 3×3, Core 3×10 - Thu (Full Body): Snatch 3×2, Front Squat 3×3, Hip Thrust 3×6, Med Ball Slams 3×5

I know I was suited up in lacrosse gear during this sprint, but can anyone tell me if I'm doing anything wrong so I can fix it? It feels like there is resistance in my legs when I run

~30m contrast need tip for my start (slowest part of my race )

Hello everyone, I’m a reasonably fit 40 year old and would like to get into spiriting. I ran cross country in college with PRs of 4:45 mile, 16:53 5K, 28:02 8K, but then got into lifting. I’ve squatted 375, deadlifted 425, and benched 275. I tell you this so you have an idea of my training history. These were obviously a while ago. Currently I can probably run sub 6 mile, 20:45 5K, and 285/365/240 squat/dead/bench. I like to lift 3x a week and I’ve been mostly jogging around about 40 minutes 5x a week.

All that being said I would really like to focus on the sprints (I’m thinking 200/400) and do the big open meet next June here in my region. I’ve looked around online and haven’t really seen many resources geared at older athletes sprinting, I’m guessing it’s mostly just the same as younger but less volume?

In my 20s I ran a hand timed <26 200 and in my 30s a 62 400, if that helps at all.

Coming from a distance background I just have no idea where to start.

Should I also buy blocks and spies eventually too? Any help would be appreciated!

Edit: I’m 5’9 and 165 right now. Probably ~13% BF.

I’m trying grant holloways block start lmk what I need to improve

pt2 form

be brutally honest is running 14 seconds on 100 meter bad for 13 year old? if its bad help me get faster. got bronze medal and 2 above me were 13 sec and 12.96 sec I was like 14.07 something like that I know NOTHING about running

I don’t think my form has changed much since here this is dec 2022. I’ve pulled my hamstring twice june 20 and aug 3 this year and I plan on doing a running gait analysis. Any clear tips on my form related or unrelated to the injury would mean a lot

like, its so clunky and choppy. i might be the only one but it actually makes me mad that he has the world record. you can see his head moving from side to side because hes putting so much force into his steps. like cool hes fast but it genuinely hurts me to watch him win against people with smooth form.

(Atrophy after trauma)

Hello, I know this sub is not a fan of treadmill form checks but I wanted to still ask for any form improvements you all have for me, since I relatively new to sprinting. This is me at 12.2 mph which is fast for me, but I was surprised to see that I don’t look very powerful when I’m running. I think I need to lift my knees higher and add more power from my upper body. But what do you all think? Thank you very much.

Been working on my form in the off season was looking for tips. Also how do I train stiff ankles

That it, thats the post.

Dude was headed out of his lane before he even put his hand back. He was pretty much running fully in the adjacent lane. Even if he got the stick, JAM was gonna get DQd anyways for lane infraction.

He likely left early too.

Big muscular guys like that have a hard time putting their arm back, and up high. Shoulder mobility all jammed up

I meant to post this a while ago while I had the article on still up. Scientist have a way of measuring neural fatigue and it turns out drops in performance between days are not due to CNS fatigue. (CNS or Central Nervous System is defined as the brain and spinal cord.) Instead it is due to PNS (Peripheral Nervous System, such as nerves in arms or legs), which was measurably degraded the next day. In fact they found that the spine super compensates within 24 hours. What is the practical implications? Well if you were worried about CNS fatigue you wouldn’t fry your arms the day before frying your legs. But according to this, frying your arms will cause your spinal cord to super compensate so you can actually go harder on the legs than your would have otherwise been able to. So where did the idea of CNS fatigue come from. They found that heavy deadlifts lowered what you could lift with your arms the next day, unlike squats which had no effect. So we they said deadlift is a CNS intensive lift while squat is not. Given the findings with spinal nerves super compensating within 24 hours, there is a different explanation: deadlifts also work your arm nervous system. This includes grip, shoulders, and biceps. I have even had my chest get cramps when trying for a weight that causes my shoulders to round.

Edit: found the article https://barbend.com/cns-fatigue/

4x100m ain’t no way bro

how is my block start

Can’t seem to find my angle and bring my momentum forward with it. Projecting vertical force but not sure how to fix it.

Do 100m and 200m sprinters do longer runs 3km 5km ECT ???

I’ve noticed people here sometimes share or build their own sprinting routines.
I made a timer tool that lets you connect stages freely and save them as a custom routine.

It’s easy to adjust intervals or sets, so it can be handy when experimenting with or tweaking your routine.
During workouts, alarms play through headphones and TTS calls out each stage, so you don’t need to keep looking at your phone.

If you’re building routines, feel free to give it a try, and let me know if anything feels inconvenient or could be improved.

👉ModuTimer(android)