Today we’re totally immersed in data—data about how well (or how much) you sleep, data about your swim, bike, and run, even live data about your blood chemistry. But as we’re starting to learn, there can be too much of a good thing. At some point data can become a boat anchor rather than a turbobooster.

Should we race by numbers or race by instinct? Which works best? As the evolution (and perhaps our reliance) on data in triathlon becomes ever greater, it seems an increasingly pertinent question.

It was also one addressed by Ironman World Championship St. George third place-finisher Braden Currie in a recent blog post. The post revealed how influential the work of his coach Ben Reszel had been in breaking down the bike course in St. George to give the Kiwi a very detailed plan of how it should be attacked.

“I have always felt that I needed to read the race and make decisions on the fly,” Currie wrote, before explaining how the additional time to prepare for the race in Utah allowed him a different approach and deep-dive analysis of what power numbers were required and when.

RELATED: How Braden Currie (Nearly) Raced the Perfect IMWC St. George

With Currie having arguably the best ride of the day—and probably the best of his life—it clearly worked. But does that hold for everyone? Is Ironman racing just a numbers game, or should intuition transcend the digital display of watts?

We asked two of the world’s most successful coaches for their view. Dan Lorang is coach to the Bora Hansgrohe professional cycling team and the statistical brain behind the recent success of Ironman world champions Jan Frodeno and Anne Haug. Siri Lindley has coached 11 world champions including past Kona winners Mirinda Carfrae (2010, 2013, 2014) and Leanda Cave (2012).

While Coach Lorang is admittedly more of a data guy, and Coach Lindley goes more by feel, there’s much more grey area between the two than you’d expect. Read on to see what each has to say.

Dan Lorang: “Can you disconnect the numbers from your feelings?”

“There are coaches who work with data, coaches who work on feel, and others who mix both. But most importantly it should depend on the athlete. Do they want to integrate data into the training and then racing? And for those who really like to stick to the numbers, can they disconnect them from their feelings?

“For example, if you want to lose weight, you look at the scales in the morning. It says one pound more than you want, is your day already done because you are so stressed? In this case, it would be better not to work with data at all!

“I have both categories in the athletes I coach. Anne, who I’ve coached for 17 years, always works by feel. The data instruction is on the training plan—bike at this power, run at this pace—but the effort is more important, whether that’s easy, medium, hard, or all out. This changes completely with Jan. By sticking to his numbers and the right zones in training, it gives him the confidence to know when he’s race ready.

“Anne races completely by feel and won’t see her watts during the bike, but will sometimes wear a watch during the run to control the pace. Jan has the numbers, so if he wants to look, he can. It’s not that he sticks specifically to data, but uses it to compare with how his body is feeling. Instead, we talk more about tactics of how the race could develop and the limitations. I.e., How much time could Jan spend over 400 watts? If he’s feeling great in the last 20 miles of the bike or riding towards Hawi [the hill ahead of the bike turnaround in Hawaii], we could try to push it within a certain power range. It’s guidance and information, but the decision is always taken by the athlete in the race.

“Data is of course helpful. Coaching most of my athletes from distance, I’m not on deck every day, and I need data to be able to analyze what’s happening to better help the athletes’ development. As well as power on the bike and pace on the run, heart rate tells you a lot about how much work the body is doing, and you can check if you’re in the right zone. During races, we might also have a cadence range for the bike, and some athletes look at stride frequency or cadence on the run too.

“I just provide tools for them to make decisions in a good way. My coaching style is always to have the athlete in the center. I want them to take responsibility, and see it as a step in their progression as professional athletes. A ‘coach say, athlete do’ strategy is not how I want to work. I know there are athletes who can only bring their best in these conditions, but I’d say it’s better to find another coach.”

RELATED: Riding With a Power Meter Will Supercharge Your Training

Siri Lindley: “Let’s get rid of this fricking thing.”

“My philosophy as a coach is to always do every aspect of training by feel and perceived effort. This has proved to be incredibly powerful. This works, and I’ve never coached any differently.

“One year, I coached five of the top professional women in the world for the Ironman World Championship in Kona. My pre-race talk was different for each because they were such different individuals.

“One wanted to break the course record and was ready to dig deeper than ever before to make that happen. Another wanted to finish the race knowing she’d strung together as many great moments as possible and was present to take it all in.

“Another was her own biggest competitor, and she was the only one that could get in the way of her having the race she dreamed of. Another needed to be reminded of all the incredible work she’d done, and this was a celebration—no pressure. Another was out to prove something to her doubters. She needed to be fired up to deliver at the highest level.

“We had no wattage goals, heart-rate goals, or pacing goals. The only goal was for each athlete to race their own race using perceived effort they had dialled into day-after-day-after-day in training. Three came in the top eight, the other two were top 15. They all trained differently. Each required a unique approach.

“This is how I have notoriously had many great athletes at the same point in time. I didn’t just get lucky, I was able to see each athlete for the individual they are, and address their specific needs—not just training needs, but emotional and mindset needs.

“When gadgets started getting big in 2008, Mirinda wanted to start using one. The first thing I noticed was that she was losing confidence and getting frustrated. It took training from being a place of empowerment—knowing your body, digging deep, going as hard as you know you can and pushing beyond that to see what’s possible—to a constant judgement zone: ‘Am I good enough? Or not good enough?’

“Finally, I said: ‘We’ve had tremendous results before, let’s get rid of this fricking thing!’ Later, when Rinny won Kona, she used the power meter, but the screen would just show her cadence. She wasn’t allowed to look at it. This goes for all the athletes I coach. They upload the file, and I use it to adjust sessions.

“After one of Rinny’s victories, Training Peaks asked if I would share her power file. They were wowed by its even distribution and asked how we used power in training. I said we only go by feel, and they were blown away.

“Here’s the thing. Say an athlete has been training with power with 30-minute efforts at Ironman watts. If the taper is managed properly—we do two weeks when they bring down their training in a very specific taper—their numbers on race-day are going to be numbers they’ve never seen before.

“If the athlete is just using power, they hold their planned 200 watts and it’s a dream come true. But what if they could be holding 210 watts because they had a great taper, it’s race-day, and the adrenaline is flowing?

“Working with power and heart-rate can put a ceiling over the athlete’s head, and they miss all the magic that’s just above, that’s totally achievable. It’s a limiter and discouraging. I want my athletes empowered, confident, and knowing exactly what a certain effort feels like, so they’ll go for that feeling on race day and reach levels they couldn’t imagine.

“Knowing the human being is the key factor to understanding what type of training brings out the best in them and will help them achieve their dreams. If something outside of the sport that really matters to them is in crisis, a coach must help them through this, and also understand the effect it will have on their physical and emotional capacity. Adjusting the training is crucial at this time.

“A beautiful gift in training this way is that the triathlon journey becomes a vehicle through which athletes truly come to know themselves and their bodies. They come to know their top values, and connect to their deeper why. All of this prepares them for life beyond the sport which is even more important.

“If you are only knowing yourself as the numbers you see on your bike or wrist, you are missing out on truly getting to know you! To me that seems like a missed opportunity.”

RELATED: Stay or Go? When to Follow the Race Plan (and When to Go for Broke)