The Core Principle and the Aggregation of Marginal Gains

A story that I love about achieving excellence is the story of Team Sky, the British Cycling team.

In 2010, Dave Brailsford was appointed to the role of Performance Director of Great Britain’s cycling team, Team Sky. At the time the team had never won the Tour de France, and it was Brailsford’s remit to turn the team around to become champions of the sport.

Team Sky put in place two principles. The CORE Principle and the Aggregation of Marginal Gains.

The CORE Principal

Brailsford and his team introduced the CORE principle to Team Sky to address the question of how to achieve excellence as human beings.

The Core Principle looked for four things in team members: Commitment, Ownership, Responsibility and Excellence.

Commitment: The CORE Principle taught that motivation changes but commitment and attitude need to stay consistent to be successful. Commitment is about having an intrinsic drive towards achieving a goal and taking ownership of your training, development and performance.

Ownership: The CORE principle of ownership is that you take initiative and have a say in what you’re doing. Brailsford says ownership is also about having an opinion and as a leader creating an open environment for transparency. Riders were encouraged to have a say in their development and their coaching programs.

Responsibility: The CORE principle of responsibility is about being clear about accountability. What are you accountable for and what are you not accountable for? What is and isn’t expected of your attitude and performance?

Excellence: The CORE Principle of excellence is about being the best you can be. What is your standard of excellence, and the standard of excellence for what you want to achieve?

The Aggregation of Marginal Gains

The aggregation of marginal gains sounds simple. It teaches that each good habit builds upon the last and compounds to produce an exponential return.

After his appointment to Performance Director of Team Sky, Brailsford encouraged team members, coaches and other team support professionals to look for the 1% margin for improvement in everything they did.

Everyone was encouraged to get back to basics and identify where a marginal improvement could be made in every aspect of cycling. This created a mindset change across the team including mechanics, coaches, and other support team members.

The team looked at optimising everything. The pillows and bedding team members slept with when on tour, the tyres on the bikes, the way everyone washed their hands, and the way meetings were conducted.

As Brailsford said:

“The whole principle came from the idea that if you broke down everything you could think of that goes into riding a bike, and then improved it by 1%, you will get a significant increase when you put them all together,”

“There’s fitness and conditioning, of course, but there are other things that might seem on the periphery, like sleeping in the right position, having the same pillow when you are away and training in different places.

“Do you really know how to clean your hands? Without leaving the bits between your fingers?

“If you do things like that properly, you will get ill a little bit less.

“They’re tiny things but if you clump them together it makes a big difference.” (1)

The team constantly measured and monitored performance based on key statistics to target any observed development areas in performance.

Using this approach Brailsford promised to win the Tour de France in five years.

No-one believed Team Sky could do it. They won it in three years.

How it works

Success is a product of what you do consistently day in and day out. It’s not about one great effort that wins the tournament. It’s about everything you do leading up to the race. Consistently turning up for training, hygiene, diet, equipment, attitude etc.

By looking for the 1% improvement in everything we do, we continue to achieve sustainable improvement over time until we reach (and often exceed) our goals.

If you want to improve your performance, it doesn’t happen overnight. It happens one step at a time and by looking for an incremental improvement every day. It’s about sustainable habit change.

The aggregation of marginal gains tells us to never miss a good habit twice. If I get up this morning and decide that I just can’t make it to the gym, that’s not going to have a huge impact on my overall fitness. However, tomorrow I need to get up and go to the gym because if I don’t, I’ll be more likely to not go to the gym tomorrow, or the next day and so on.

The aggregation of marginal losses works in the same way. We do something unproductive or unhealthy today, and that’s okay as long as we don’t repeat the bad behaviour tomorrow, because if we do, it will soon become a bad habit that we repeat daily.

Our performance is the sum of our habits. The things that we do each day. If we look to continually find a 1% improvement in everything we do, and keep repeating those new habits our performance will continue to improve.

“Sport is about continuous improvement, it’s about getting better,” said Brailsford. “It’s about being better next year than you are this year. It’s a bit like Formula One. You have a car and the designers might say ‘we can’t think how we’re going to make this any better’. But ultimately you can. And that’s what we’ve got to do. We’ve got to keep looking, researching and working – trying things. And that’s what it’s all about.”

“Everyone is back at square one. Nobody has an advantage because of what we did last year. No one gets a 10-mile start or anything. We’re all absolutely back to zero. And unless you’ve done the work – unless you’ve put in and unless you’ve done what it takes – then you’re going to suffer. There’s no hiding place in this sport.” (2)

Questions for you to reflect on

What are you accountable for in your role?

What are you not accountable for? (This is a great question to remind us to keep our noses out of things that don’t require/benefit from our attention!!)

What is and isn’t expected of your attitude and performance?

What is your current standard of excellence?

What is the standard of excellence you wish to achieve?

What’s the 1% improvement you can make today? (Hint: Ask yourself this question each day)

Let us know how you go,

Cholena xo


Clear, J n.d., This Coach Improved Every Tiny Thing by 1 Percent and Here’s What Happened Available from: [31 December 2015]

Team Sky Team Principal. Available from: [31 December 2015]

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s