How Leos Mikulka Returned 409% in the 2024 US Investing Championship

Leos Mikulka, a software solutions architect from Prague, finished third in the 2024 US Investing Championship with a 409.6% return across 178 trades. A former professional footballer for the Czech Republic national team, Mikulka built his edge by combining aggressive swing trading with systematic risk management. Here’s how he did it, and what you can learn from both his wins and his mistakes.

From Professional Football to Professional Trading

Leos Mikulka’s path to a championship-caliber trading year didn’t start in finance. He played professional football for the Czech Republic national team before transitioning into IT, where he now works as a software solutions architect in Prague. Trading started as a side pursuit, something he could do around his day job.

Eight years of screen time and a lot of trial and error shaped his current approach. The turning point came in 2019, when Mikulka joined Mark Minervini’s Private Access program and attended the Master Trader Program workshop. That’s where the mental side of trading clicked for him: risk management, discipline, and avoiding revenge trading after losses.

The competitive structure of the US Investing Championship gave Mikulka a framework to push himself. He entered the championship previously with a 300%+ return, but 2024 was the year everything came together in a bigger way.

The Numbers Behind 409%

Championship results are verified and audited, so there’s no ambiguity about what Mikulka accomplished. His final return of 409.6% placed him third in the 2024 US Investing Championship, competing in the $20,000+ accounts stock division.

A 60.7% win rate is solid but not extraordinary on its own. What drove the outsized return was the risk-reward ratio on his winning trades. Instead of averaging 20-25% on winners (which would be strong for most swing traders), Mikulka’s average winning trade returned roughly 9-10%, but he sized aggressively enough that the compounding effect was massive. When he was right, he was right with size.

His average losing trade lasted just five days. Cutting losers fast while letting winners run for an average of 20 days created the asymmetric profile that championship-level returns require.

How Mikulka Finds and Trades Market Themes

Mikulka is a swing growth trader at his core. He looks for stocks in strong uptrends that are forming constructive bases, then enters on breakouts with a defined risk point. But what separates his approach from generic breakout trading is his focus on sector rotation and market themes.

Rather than screening the entire market indiscriminately, Mikulka narrows his focus to the sectors and themes showing the most institutional interest at any given time. In 2024, that meant AI-related semiconductor names, nuclear energy plays, and IPO stocks that were setting up after their initial runs. By identifying where the money was flowing, he could concentrate his firepower on the highest-probability setups.

This thematic approach also informed his sell decisions. When a sector started losing steam or rotating out of favor, Mikulka used that as a signal to tighten stops or reduce exposure, rather than holding and hoping. Understanding market cycles kept him on the right side of the bigger trend for most of the year.

Position Sizing and Risk Management

Position sizing is where Mikulka’s approach gets aggressive, and where the 409% return becomes possible. His standard position size sits at 20-25% of his account. When conviction is high and the setup is clean, he’ll scale up to 50-70% of his account in a single name.

That’s not a typo. At those concentration levels, a small adverse move can create a significant equity drawdown. A 200% position (achieved through margin) with a 3.5% stop means 7% of your account is at risk on a single trade. Mikulka is fully aware of this math. It’s a deliberate choice, not carelessness.

His average stop sits around 3%, which is tight for swing trading but consistent with the stop placement techniques used by top CANSLIM and momentum traders. For setups where a clean fixed stop isn’t possible, he uses staggered stops: a very tight 1-2% stop on a portion of the position, with a wider 8-10% stop on the remainder.

The critical detail is that Mikulka adjusts his sizing dynamically based on how he’s trading. When trades are working and he’s in a hot streak, he increases size to capitalize. When he hits a string of losses, he pulls back. This approach ensures the biggest positions coincide with the strongest environments.

Key Trades: ARM and SMR IPO Breakouts

Two trades stood out in Mikulka’s 2024 championship run: Arm Holdings (ARM) and NuScale Power (SMR). Both were IPO stocks that built constructive bases before breaking out on strong volume.

Arm Holdings (ARM)

ARM went public in September 2023 and spent months building an IPO base. For Mikulka, the key was patience. He waited for the base to mature, for volume to contract during consolidation, and for a clear pivot point to form before entering. When ARM broke out, he was ready with size.

ARM

The ARM trade is a textbook example of how IPO bases can produce explosive moves when they coincide with a strong market theme. The AI semiconductor narrative provided a tailwind that Mikulka recognized early and positioned for aggressively. His risk management on the trade involved scaling in as the breakout confirmed, then gradually reducing the position into strength as the stock extended from its exhaustion extension.

NuScale Power (SMR)

SMR represented a different thematic play: nuclear energy. As the narrative around small modular reactors gained traction in 2024, NuScale Power (SMR) built a base and then broke out on increasing institutional interest. Mikulka identified the theme early and used the same framework he applied to ARM: wait for the base, identify the pivot, enter with conviction.

SMR

Both trades share a common thread. Mikulka wasn’t chasing headlines. He was identifying structural setups within trending themes and waiting for the right entry. That discipline, combined with the willingness to size up when conviction was high, turned what could have been modest swing trades into meaningful contributors to his 409% year.

Selling Into Strength and Free Rolling

One of the hardest parts of trading is knowing when to sell. Mikulka approaches this systematically through two primary strategies: selling into strength and free rolling positions.

Selling into strength means taking partial profits while a stock is still moving in your favor, rather than waiting for a reversal to signal the exit. Mikulka sells a portion of his position once the trade hits a favorable risk multiple, then adjusts stops higher on the remaining shares. This locks in profits and reduces risk on the overall position.

This approach is particularly effective for aggressive traders like Mikulka who take concentrated positions. By de-risking early through partial sales, he creates scenarios where even a stop-out on the remaining position results in an overall profitable trade. It’s a way to stay aggressive on entry while being disciplined about protecting gains.

Mikulka also uses his trading journal to track average win percentages and hold times, which informs his sell targets. If his average winner gains 9-10%, he starts scaling out once a trade approaches that threshold, while leaving room for the occasional outsized move. Knowing your own statistics turns selling from a guessing game into a repeatable process.

The December Drawdown: Lessons from a 52% Drop

No championship year is without its scars. Mikulka’s came in December 2024, and it was severe.

At his peak, Mikulka’s account was up over 465% for the year. Then seven consecutive stop losses hit in rapid succession. The compound effect of large positions getting stopped out back-to-back dragged his account down by 46.6% from the top. He’d been progressively increasing position sizes throughout the year, and by December he was holding 200% positions on margin. When the market turned, the math was brutal.

In the final days of December, Mikulka made a calculated decision to risk 10% of his account across multiple day trades, attempting to push back above 500% for the year. It was an all-or-nothing play, and the conditions weren’t favorable. The strategy failed, and his final return settled at 409.6%.

Mikulka doesn’t necessarily regret the attempt. But the episode illustrates a reality that every aggressive trader faces: the same concentration that produces triple-digit returns also creates the potential for steep drawdowns. The lesson isn’t to avoid sizing up. It’s to understand what you’re signing up for when you do, and to have a plan for when it goes wrong. Understanding your risk management framework before the losses start is what separates a drawdown from a blowup.

Trading Psychology: The 80% Nobody Talks About

Mikulka believes that trading psychology accounts for 80% of success, with technical skill making up the other 20%. Some traders argue the psychological component is even higher, closer to 90%.

This isn’t empty talk for Mikulka. He learned the hard way what revenge trading can do to an account, and credits the mental training from Minervini’s Master Trader Program with helping him develop the discipline to walk away after losses instead of doubling down. Building a winning trader’s mindset was as important to his results as any chart pattern or screening tool.

His practical approach to managing the mental side includes keeping a detailed journal, sticking to a predefined trading plan before the market opens, and reducing size after a string of losses rather than trying to make it back immediately. These aren’t revolutionary concepts. But executing them consistently under pressure is what separates a 400% year from a blown account.

For traders looking to develop their own psychological edge, Mikulka’s advice is straightforward: respect the risk, know your numbers, and don’t trade when you’re confused. Simplicity and self-awareness beat complexity every time.