Running News Daily

The hardest part of running training theory is that every athlete is their own N=1 study. We have individual inputs-training volume, intensity, etc. We have individual outputs-time to exhaustionp, VO2 max, race results. But the line connecting input to output will always be a best guess, because we have way too many confounding variables (age, stress, training background, muscle fiber typology) and no way to look under the hood to see exactly what's happening (humans prefer not to be dissected).

Even for a single athlete using different training interventions over time, there is not enough data to reliably infer what causes what. That training plan could have caused a world championship. Or it could have been the base built in that lower-intensity approach a year ago, mixed with better fueling, all combined with an optimal day in the menstrual cycle.

So how do we know what works? 

Well, we do have a baseline understanding of physiology. While humans vary substantially, we're all a similar assortment of semi-organized chemical interactions that love the show Ted Lasso. But that still raises the measurement problem-how can we actually know what training is best with this deluge of uncontrollable variables? It's enough to make any coach pull their hair out, which may itself be an advantageous adaptation. Receding hairlines are built for aerodynamic speed, I tell myself.

While we may never be able to know the optimal approach for each individual, we can hypothesize what works across the population. N=1 sucks. But add up thousands of Ns, and we're getting somewhere. Bad for scrabble, good for training theory. Nn-nn-nn-nnn, hey hey heyyy, good science.

And when you add up all those Ns in running, looking at training logs of top performers, you'll notice something curious. Doubles. Lots and lots of doubles.

Doubles in Practice

A 2019 study in the Journal of Strength and Conditioning Research looked at 85 elite athletes over their first seven years of serious training to draw conclusions about the type of runs associated with top performance. Volume of easy runs had the highest correlation with performance, from 0.72 at 3 years to 0.68 at seven years. These findings were backed up by a 2020 study in the European Journal of Sports Science. Neither of those studies discuss doubles specifically, but I'd bet the dog and the car (as implied by the first thing, a Subaru) on some of that volume being accumulated with multiple runs in a day.

For example, a 2019 study on the Ingebrigtsen brothers indicated that they accumulated 150 to 160 kilometers a week onget this13-14 separate sessions. They sometimes do multiple harder workouts in a single day. And brother Jakob won the 1500 meter gold medal in Tokyo.

The same goes for athletes coached by Renato Canova, famous for his "block" training days of two hard workouts, plus countless easy doubles. Before medaling in the Olympic Marathon, Molly Seidel did 6 doubles most weeks. I bet there are more running Olympians who do triples (used in some East African training camps) than train solely with singles. 

Last week's article on cross-country ski training cited many studies (an excessive number of studies) about the high proportion of extremely easy training at the top end of that sport. Some of the greatest champions do 90%+ of their training at low heart rates! As outlined by a 2010 study in the Scandinavian Journal of Medicine & Science in Sports, skiers (and runners) accumulate aerobic volume to increase in mitochondrial content and capillaries around muscle fibers, improve metabolic function at both high and low intensities, and encourage a more economical use of oxygen to power performance at all intensities as well. All of that corresponds to faster race performances, even in events that are just a few minutes long.

But if it was just about volume, why aren't we seeing top runners rely more on massive singles? That's what bikers do for the most part: several tiny espressos, one big ride. Meanwhile, swimmers do tons of doubles, as do skiers. That's interesting! So what connects running and swimming and skiing, but not biking? My guess is that it's related to the biomechanical demand of the sport varying significantly at slow paces, plus injury risk. Biking is the same if you do it with low power or high enough power to mine Bitcoin in an environmentally responsible way (quads will save the rainforests?). For running, meanwhile, overload those biomechanical patterns and athletes may get inefficient, even if they are able to avoid injury.

So we're trying to add up to a big aerobic number (adjusted for individual background), while balancing overall stress for long-term adaptation. But overemphasizing long singles may have diminishing returns due to the demands of running. 

Doubles help solve the math equation. 

But is it just about the extra volume? I doubt it. 

Doubles may provide a hormonal stimulus that enhances adaptation, they may increase adaptation markers and protein expression associated with better performance, they may improve glycogen replenishment, they may even have some fascinating relationship to epigenetic signaling. A 2012 study on mice found that 3 x 10 minute runs in a single day led to the same adaptations as a 30 minute run, but possibly with slightly larger increases in expression of one protein (TSP-1). What would that type of study look like in humans? Unfortunately, finding out would require dissection. And that's the type of lopsided trade that would only appeal to the New York Mets.

Whatever the exact reasoning, thousands of world-class athletes have come to the conclusion that doubles are key on the track and roads. However, they're sometimes less common in trails and ultras. I have two theories for the cause of that offset.

First, trail running relies heavily on resilience to fatigue from variable musculoskeletal loading patterns. The track is an aerobic system contest, the trails involve the same aerobic pathways with a wrinkle-it doesn't matter how strong your aerobic system is if your legs are Jello. Musculoskeletal damage (and thus, potential adaptation after recovery) accrues over longer runs, so perhaps the long singles create resilient monsters (assuming an athlete doesn't break first).

Two, the margins in trail running are not as narrow as on the roads and track. Our sport is messy, full of rocks and roots and airplane arms, so the champions don't need to find every single possible advantage. A 0.1% improvement in aerobic power might be swallowed up by a 10% improvement from not eating sh*t on a descent. (That also gives me hope that doping is less common in trail running than in a sport like cycling.

How To Add Doubles

While doubles work for pro athletes, I have seen in coaching that they can work for almost anyone, subject to a few disclaimers. First, the body knows stress, not miles. A double can be counterproductive if it adds even an ounce too much to the stress scales. Only double if you have the time, energy, and life force to spare.

Second, increasing volume increases injury risk. It's hard to run a PR with an achilles that sounds like a creaky doorway. 

Third, adaptation is a high-stakes game. Overloading stress in moderation followed by recovery can lead to breakthroughs. But overloading a bit too much can lead to stagnation and regression. Some world-class athletes are likely chosen partially because they are genetic anomalies with adaptation under high chronic stress loads. So make sure you're always listening to your body.

Given those risks, my co-coach Megan and I introduce doubles with five guidelines. This will be the next topic for "Sexy Science Corner" on our podcast, so listen when that comes out for more info.

One: Keep it very easy-up to 2x your 5k pace

If the goal is the aerobic stimulus while balancing stress, almost no pace is too slow. I personally do my doubles without a GPS watch, partially because it may auto-pause due to how slow I go. If your normal easy pace is 8 minutes per mile, you can make it 9 or 10 minutes per mile, especially to start. Molly Seidel often does them at 8+ minute pace, with a marathon pace in the mid-5s. I have seen some pro runners in Boulder doing them at what looks like 10 minute pace. Glorious prancy ponies! Just focus on good form-light on your feet with quick strides.

Two: Keep it short-20 to 30 minutes is plenty

There is some evidence that the productive hormonal stimulus of running rises most rapidly in the first half-hour, before leveling off (and sometimes reversing, though it's debated and individual-dependent). Many athletes describe feeling refreshed after a quick afternoon shake-out. For trail runners, we really love doing some of these sessions on the "treadhill" to reduce impact and get climbing-specific biomechanical loading.

Three: At least a few hours after your first activity

Glycogen replenishment is a key element in doubles, so some fun food and a few hours is plenty. Canova blocks sometimes involve tinkering with glycogen levels for elite male athletes, but we have seen that backfire.

Four: Add them on workout days first, aerobic days next

Easy doubles on workout days may maximize adaptation benefits, plus there is a greater endurance stimulus. Once an athlete is adapted to the approach, we'll occasionally have them run more moderately on some workout-day doubles or treadhills (sometimes even with structured workouts like Canova blocks, but that's a training element you should only add at the direction of a coach due to the high risk of injury and overtraining). Don't double on long run days, which may overwhelm glycogen replenishment and increase breakdown rates. Any double could be replaced by easy cross training as well, which should accumulate aerobic adaptations at similar rates, with lower injury risk.

Five: All doubles are optional

There is no such thing as a mandatory double for our athletes. The main training session is what matters most, and tons of our team members have won some of the biggest races in the world without any doubles at all. So listen to your body. Are you dreading it? Skip. Do you have any niggles, even the smallest whisper from a gnat's ass? Chill. Affect sleep, family, work? Bag it. Does it slow down your recovery for the next day? It's OK to give it a couple weeks for adaptation, but if that persists, nix doubles until you wake up the next day feeling as strong or stronger than you would otherwise.

Many athletes we coach will see this general weekly structure on their peak build weeks, when life stress is low, and health is perfect. Peak ultra builds usually involve fewer (if any) doubles, in order to maximize the musculoskeletal adaptation stimulus, as described above.

Monday: rest and recovery

Tuesday: easy run and hill strides (6-12 miles)

Wednesday: workout (8-13 miles) and optional double/treadhill (2-4 miles)

Thursday: easy run (6-12 miles) and optional double/treadhill (2-4 miles)

Friday: easy run and optional hill strides (3-8 miles) or x-train/rest

Saturday: Long run (10-25 miles)

Sunday: easy run and hill strides (6-15 miles) and optional double/treadhill (2-4 miles)

The big thing to remember: doubles are 100% not necessary. But then again, running isn't really necessary either, in the big scheme of the universe. Doubles, like run training in the first place, is all about exploring the limits of your potential by doing something that seems moderately unreasonable.

Most Olympic marathoners spend their youth focused on running. They join track clubs, compete in national championships, and pursue the sport from an early age.

Julia Mayer’s journey was very different.

Today, Mayer is Austria’s marathon record holder, a multiple national record holder on the roads, and an Olympian. Yet for much of her athletic life, running was not her primary sport.

For 16 years, she played soccer.

Then she discovered something that would change her life.

“I noticed that I was really fast in the fun runs and that it was really, really fun,” Mayer said when reflecting on her transition from soccer to distance running.

What began as curiosity quickly became a passion. She eventually made the bold decision to leave soccer behind and focus entirely on running. It was a move that surprised many people around her, but Mayer believed she had found her true athletic calling.

The decision proved to be the right one.

Within a few years, Mayer developed into one of Europe’s top marathon runners. Her steady improvement carried her from local races to the international stage, where she began rewriting Austria’s record books.

She now holds Austrian records in the marathon, half marathon, and road 10K. Her marathon best of 2:26:08 established her as the fastest female marathoner in Austrian history. Her performances in the half marathon and 10K have further cemented her place among the country’s all-time great distance runners.

Her rise culminated with qualification for the 2024 Olympic Games in Paris.

Competing in the Olympic marathon represented the realization of a dream. On one of the most challenging marathon courses ever used for the Olympics, Mayer ran courageously against the strongest field in the world and finished 55th in her Olympic debut.

Behind the scenes, success has come through extraordinary dedication. During marathon preparation, Mayer trains twice a day and covers approximately 200 kilometers, or 124 miles, each week. The workload demands discipline, patience, and a deep commitment to continuous improvement. 

What makes her story especially inspiring is not simply the records or the Olympic appearance.

It is the fact that she found her greatest talent later than many elite runners.

In a sport where athletes are often identified at a young age, Mayer’s journey serves as a reminder that potential does not always reveal itself early. Sometimes it takes years of experience, a willingness to try something new, and the courage to follow a different path. 

The former soccer player who once chased a ball across a field is now chasing history on the roads of Europe.

And according to those closest to her, her best performances may still be ahead.

For runners of every age and ability, Julia Mayer’s story delivers a powerful lesson: it is never too late to discover what you are capable of.

From soccer player to Olympian, her journey proves that remarkable achievements can begin when least expected.

Megan Keith produced the performance of her career in Oslo on Thursday night, shattering one of Scotland’s longest-standing distance running records and cementing her place among Britain’s greatest female 3000m runners.

The 24-year-old clocked a sensational 8:28.35 over 3000m, breaking the Scottish outdoor record that had stood for nearly four decades. In doing so, Keith eclipsed the previous mark of 8:29.02, set by Scottish legend Yvonne Murray back in 1988, ending a record reign that had lasted 38 years.

Keith’s breakthrough run was more than just a national record. The performance also propelled her to third on the UK outdoor all-time list, placing her behind only two of Britain’s most celebrated distance runners — Paula Radcliffe, who leads the rankings with 8:22.20, and Laura Weightman, whose 8:26.07 remains the second-fastest outdoor mark by a British woman.

The significance of Keith’s achievement is amplified by the calibre of athletes she now joins in the record books. For decades, Murray’s mark stood as one of Scottish athletics’ most untouchable records, surviving generations of elite competitors. Keith has now succeeded where many outstanding runners have fallen short, announcing herself as one of the leading distance talents in British athletics.

Her time also compares favourably with the best performances produced indoors. Olympic medallist Laura Muir ran 8:26.41 indoors in Karlsruhe in 2017, underlining just how exceptional Keith’s outdoor effort in Oslo truly was.

The run continues a remarkable rise for the Scottish star, whose progression over recent seasons has transformed her from a promising prospect into a genuine force on the international stage. Running with confidence and composure against elite competition, Keith demonstrated both the speed and endurance required to challenge the very best in Europe and beyond.

With the World Championship season gathering momentum, Keith’s record-breaking display sends a powerful message. Not only has she etched her name into Scottish athletics history, but she has also established herself as a serious contender in one of the sport’s most competitive events.

In Oslo, Megan Keith did far more than break a record. She ended a 38-year wait, climbed into the upper echelon of British distance running, and delivered a performance that may prove to be a defining moment in her career.

British middle-distance talent Phoebe Gill took another significant step forward in her return to top form, producing a determined victory over 800 metres at the Meeting de Marseille in France on Wednesday.

Competing in challenging, wind-affected conditions, the 19-year-old demonstrated both resilience and composure as she held off a late charge from Switzerland's Veronica Vancardo to secure the win in 2:00.81. Vancardo finished just three hundredths of a second behind in 2:00.84, underlining the fiercely contested nature of the race.

While the margin of victory was narrow, the result represented another encouraging milestone for Gill as she continues to rebuild momentum following her injury setback. The young Briton showed impressive race awareness and strength in the closing stages, maintaining her advantage despite the difficult conditions that made fast running a challenge throughout the evening.

The Marseille triumph adds to a growing body of evidence that Gill is steadily progressing toward her best form. Earlier in her comeback campaign, she clocked 2:01.50 for 800m in Bydgoszcz before demonstrating her versatility with a strong 4:05.53 performance over 1500 metres at the BMC Grand Prix meeting in Trafford.

Those performances have highlighted not only her improving fitness but also her ability to compete across multiple distances as she carefully builds her season. The Marseille victory now provides further confirmation that the European junior star is moving in the right direction.

Gill emerged as one of Britain's most exciting middle-distance prospects through a series of breakthrough performances as a teenager, earning widespread recognition for her fearless racing style and remarkable maturity. Injury temporarily interrupted that upward trajectory, but her recent results suggest she is steadily rediscovering the form that made her one of the sport's brightest young talents.

With each race, the signs of progress become increasingly evident. Winning in difficult conditions and under pressure from a quality field is often a stronger indicator than a fast time alone, and Gill's latest success demonstrated exactly those qualities.

As the summer season gathers pace, the Marseille victory offers another confidence boost for the British teenager, whose return continues to gain momentum. If her recent progression is any indication, Gill could soon find herself back among the leading names on the European middle-distance circuit. 

The NCAA Track and Field Championships delivered a moment few could have predicted as Ja’Kobe Tharp produced one of the most astonishing performances in the history of sprint hurdling, rewriting the record books in spectacular fashion.

Competing in the opening round of the men’s 110-meter hurdles, the Auburn star stunned the athletics world by clocking an incredible 12.75 seconds, becoming the first athlete ever to break the 12.80-second barrier. In doing so, he eclipsed the long-standing world record of 12.80 set by Aries Merritt in 2012, a mark that had stood as one of the sport’s most revered achievements for more than a decade.

What makes Tharp’s breakthrough even more remarkable is the scale of his improvement. Entering the championships, the defending NCAA and U.S. champion had recorded a season-best of 13.05 seconds. Yet under the brightest spotlight, he unleashed a performance that exceeded every expectation, slicing an extraordinary 0.26 seconds from his personal best in a race that instantly became one of the greatest ever run.

The achievement sent shockwaves throughout the track and field community. While Tharp arrived in Eugene as one of the leading contenders for the NCAA title, few envisioned a performance capable of redefining the limits of the event. Instead, the American hurdler delivered a race for the ages, combining flawless technique, explosive speed, and impeccable rhythm from the first hurdle to the finish line.

The historic run not only secured his place in athletics history but also transformed the outlook of the championship. With the world record now in his possession, Tharp advances to the final as the overwhelming favorite, carrying momentum that could make an already unforgettable weekend even more extraordinary.

For years, the 12.80 barrier appeared untouchable. On a stunning day at the NCAA Championships, Ja’Kobe Tharp proved otherwise, producing the kind of performance that reminds fans why sport remains so unpredictable. In a matter of seconds, he turned a routine qualifying round into a landmark moment that will be remembered for generations.

The world record no one saw coming is now a reality—and Ja’Kobe Tharp is the man who changed history.

A new chapter in middle-distance running may have begun in Oslo after American teenager Cooper Lutkenhaus produced one of the most remarkable performances of the season, narrowly defeating reigning Olympic champion Emmanuel Wanyonyi in a thrilling men's 800m contest at the Diamond League meeting.

The 17-year-old sensation shocked a world-class field by crossing the finish line first in a race that came down to the smallest of margins. After an intense battle over the final metres, Lutkenhaus held off Wanyonyi by just one hundredth of a second, producing a dramatic finish that left the packed stadium in disbelief.

From the opening lap, the pace was relentless as the leading contenders positioned themselves for a fierce showdown. As the athletes entered the home straight, Wanyonyi appeared poised to unleash his trademark finishing kick. However, Lutkenhaus refused to be intimidated, matching the Olympic champion stride for stride before producing a perfectly timed lean at the line to secure a historic victory.

The result marks a breakthrough moment for the young American, who continues to establish himself as one of the brightest talents in global athletics. Defeating an Olympic champion at a Diamond League event is a feat many athletes spend entire careers pursuing, yet Lutkenhaus achieved it before reaching adulthood.

For Wanyonyi, the narrow defeat does little to diminish his status as one of the world's premier 800m runners. The Kenyan once again demonstrated his exceptional class and competitiveness, pushing the race to a world-class standard and forcing his young rival to deliver the performance of a lifetime.

Beyond the result itself, the race offered a glimpse into what could become one of the sport's most exciting rivalries in the years ahead. With established stars and emerging talents now pushing each other to new heights, the men's 800m continues to evolve into one of athletics' most captivating events.

On a memorable night in Oslo, the spotlight belonged to Cooper Lutkenhaus. At just 17 years old, he stood toe-to-toe with an Olympic champion and emerged victorious, announcing himself to the athletics world in spectacular fashion.