The 3-Hour Longevity Workout: What a Sports Doctor Prescribes

Iran deal news. Oil crashed 10%. AMD surged 20%. S&P above 7,300 for the first time. Records everywhere.

The quick scan: Wednesday was the session the market had been waiting for since late February. Axios reported that the US and Iran were close to a deal that would include a moratorium on nuclear enrichment and restore trade through the Strait of Hormuz. Oil crashed nearly 10%. Every sector except energy closed higher. AMD's 20% surge on AI data centre demand and Disney's 5% earnings pop added fuel. The S&P 500 crossed 7,300 for the first time in its history. Trump later tempered expectations, calling a deal "perhaps, a big assumption" – but markets had already priced in significant relief.

S&P 500: +1.46% to 7,365.12 – the first-ever close above 7,300 and a new all-time record; the index has now rallied more than 15% from its war-period low and sits more than 2% above its pre-war high
Dow Jones: +1.24% to 49,910.59 – gained 612.34 points; Disney surged 5% on earnings; Corning soared 17% on a Nvidia manufacturing partnership; Arm Holdings jumped 13% ahead of its earnings report; the Dow briefly tested 50,000
NASDAQ: +2.02% to 25,838.94 – a new all-time record; AMD's 20% surge on AI data centre demand was the session's standout; Super Micro Computer +15%; Nvidia, Micron, Intel and Sandisk all added 2–3%+; the NYSE Semiconductor Index gained more than 4%, bringing its YTD gains to 60%.

What's driving it: Two stories converged. The Axios Iran deal report – a nuclear moratorium and Strait reopening – removed the war's biggest structural overhang in a single session. Oil's near-10% collapse reflects how completely that overhang had been priced in. AMD's blowout quarter – revenue up 38% year-on-year, guidance raised sharply – validated the AI infrastructure thesis with hard numbers. The semiconductor YTD gain of 60% reflects a sector that has been consistently right about where demand was heading. VIX fell to 16.20.

Bottom line: S&P above 7,300 for the first time. Trump's "big assumption" caveat means the deal isn't done, and the Strait remains technically closed. But markets have decided the trajectory of this war has fundamentally changed. The investors who held through the noise now have 60% semiconductor gains and a new all-time high to show for their patience.

You're Probably Only Getting Half the Longevity Bang for Your Buck

The scoop: Three hours a week. That's it.

Dr Kevin Sprouse, owner of Podium Sports Medicine and medical advisor to longevity clinic Eternal, has spent a decade working with elite athletes. He told Business Insider that the same science applies directly to the rest of us – and his prescription for a longer, healthier life takes about three hours a week. The catch: those hours need to be structured across three specific types of exercise. Most people are only doing one or two of them.

"You're hitting different effort levels and getting a different stimulus with each one of them to really round it out," Sprouse said.

The three parts are Zone 2 cardio, interval training, and strength work. Each targets a different physiological system. Each is necessary. And understanding why helps you understand how to use your limited exercise time most effectively.

Part 1: Zone 2 cardio – building the engine.

Zone 2 is the foundation. Everything else depends on having it.

Zone 2 means exercising at 60–70% of your maximum effort – the pace at which you can hold a conversation without getting breathless. A brisk walk, a light jog, cycling at moderate pace, swimming steadily. You should feel like you're working, but not working hard.

The physiological target is VO2 max – the measure of how efficiently your body can use oxygen during exercise. VO2 max declines by roughly 10% per decade after 25, and more steeply after 50. It's one of the most powerful predictors of longevity that medicine has identified. Raising it doesn't require extreme training – it requires consistent, low-intensity aerobic work over time.

Sprouse describes Zone 2 as building "the machinery that allows you to get fitter."

The time split depends on your schedule. If you have limited hours, aim for roughly 50% of your exercise time in Zone 2. If you have more time available, push Zone 2 toward 80% of total training volume, with 20% at higher intensity.

Part 2: Interval training – raising your ceiling.

If Zone 2 builds the engine, interval training raises the ceiling on how hard you can use it.

The mechanism is the lactate threshold – the point at which your body can no longer clear lactic acid as fast as you're producing it. When you cross this threshold, oxygen runs low, your muscles tap into glycogen reserves, your limbs get heavier, and the effort becomes sustainable only for a limited time.

"Lactate threshold is the true measure of fitness in the moment," Sprouse said. "That's when you're on a running clock of how long you can sustain that effort."

The goal of interval training is to push that threshold higher – to delay the point at which the running clock starts. Short, hard bursts of effort, recovered, and repeated. Sprouse recommends varying the sessions: 30 seconds of all-out effort with rest periods; the next session, 3–5 minutes at a hard pace; another session at something closer to race pace for 10 minutes.

Part 3: Strength training – the one most people skip.

Cardio alone is not enough.

Sprouse is direct about this: strength training is essential for longevity, not optional. It strengthens muscles, controls blood sugar, prevents injuries, and – perhaps most importantly – directly supports the cardiovascular fitness built in parts one and two.

"To build VO2 max, you have to have muscle size. Lower fat means higher VO2 max," Sprouse said. "All these things come together in this one number, and it's great for benchmarking against the population where you stand."

The good news: you don't need much. Sprouse recommends two days a week, and notes that with the right focus, you can be in and out of the gym in 30 minutes and still make meaningful progress. The key is compound movements – squats, deadlifts, presses – that work multiple muscle groups in a single exercise. These give the most physiological return per minute in the gym.

The fourth element: recovery.

Sprouse adds one more observation that isn't a workout at all.

"The thing that the world's best do better than the rest of us is recover," he said.

Recovery – sleep, nutrition, deliberate rest between sessions – is what allows adaptation to occur. Without it, training stimulus produces fatigue rather than improvement.

On nutrition, Sprouse is straightforward: eat enough protein, carbohydrates, and total calories to fuel your activities, while avoiding processed foods and refined sugars. "We'll move the needle partially with exercise and partially with nutrition. If you just address one or the other, you're only getting half of the bang for the buck."

What this looks like in practice for a week.

Three hours. Here's one way to distribute it:

• Monday: 30 minutes strength (compound movements, moderate weight, full-body)

• Wednesday: 45 minutes Zone 2 cardio (brisk walk, cycle, swim – can hold a conversation)

• Thursday: 30 minutes interval training (30-second hard efforts with recovery, or 3-minute hard intervals)

• Saturday: 45–60 minutes Zone 2 (longer, slower – the aerobic base-building session)

• Sunday: 30 minutes strength (or swap with a second interval session if strength was done Monday)

This isn't the only valid distribution – it's an illustration of what three structured hours looks like across a week. The key is that all three elements are present, that Zone 2 dominates the cardio time, and that intensity is varied rather than uniform.

Actionable takeaways for L-Plate Retirees:

• Zone 2 is the foundation everything else depends on. If you only have time for one type of cardio, make it Zone 2 – the pace at which you can hold a conversation without gasping. This builds VO2 max, which is one of the strongest predictors of longevity that medicine has identified, and which declines significantly after 50 without deliberate training.

• Know your Zone 2 pace before you assume you're doing it. Most people who think they're doing Zone 2 are actually working harder than that. The conversational test is reliable: if you can speak a full sentence without pausing for breath, you're in Zone 2. If you're struggling to complete a sentence, you've drifted into a harder zone.

• Intervals and steady cardio target different things. Zone 2 builds aerobic capacity. Intervals raise your lactate threshold – the ceiling on how hard you can work before fatigue takes over. You need both because they produce different adaptations. Doing only one leaves the other underdeveloped.

• Two strength sessions a week is enough – if they're focused. Sprouse says 30 minutes, twice a week, focused on compound movements, is sufficient to deliver meaningful strength and longevity benefits. Squats, deadlifts, rows, presses. The goal is functional strength, not bodybuilding volume.

• Recovery is part of the formula, not a break from it. Sleep quality, eating enough protein and carbohydrates, and leaving adequate rest between hard sessions are what allow training to produce adaptation rather than just fatigue. Skimping on recovery blunts the benefit of the exercise.

• The 80/20 and 50/50 splits are practical guides. If you have more time, 80% of cardio in Zone 2 and 20% at higher intensity is optimal. If time is tight, a 50/50 split between Zone 2 and intervals still captures the core benefits. The exact ratio matters less than having both present consistently.

Your Turn:
Zone 2 – the conversational pace that builds the aerobic base – is something most people either don't do at all or do without knowing what it is. Is it part of your current exercise routine, and did the "hold a conversation" test match where you thought your effort level was?
Sprouse's observation that elite athletes do recovery better than the rest of us is easy to dismiss as something for professionals. But sleep, eating well, and rest between sessions are available to everyone. Is recovery a gap in how you think about your fitness?
The three-part formula is simple in principle – Zone 2, intervals, strength – but most people are doing only one or two of the three. Which element is missing from your current week, and what would it take to add it?

👉 Hit reply and share your story – your insights could inspire fellow readers in future issues.

If today's issue helped you think about your three hours differently, consider supporting L-Plate Retiree on Ko-fi.