As technical advisor to the Danish Rowing Federation, Jensen has worked with elite rowers for many years, both within Denmark and internationally. Among his studies, Jensen has looked at force application during individual strokes. It is here where he saw an interesting pattern emerge. From year to year, he found that each athlete’s force curve barely changed. He could identify rowers simply by looking for their specific force curve 'fingerprint'.

“Almost every rower,” says Jensen, “had a virtually identical power profile for their stroke from one year to the next when assessed in the middle of a six minute all-out test.” Out of this group of experienced international rowers, Jensen recalls only one who made any real change to her fingerprint. “She had really worked a lot to change her profile, but during maximal tests, only a minor change was observed.”

Force curves in elite rowers © Kurt Jensen


Force curves in elite rowers © Kurt Jensen

 [image: Force curve graphs for two different elite athletes. Kurt Jensen has tracked a number of athletes over the years and says that a rower’s force curve is like a fingerprint that often changes very little over time.]

The desire of both coaches and athletes to maintain an idealised force curve during an all-out performance is a quest that can last an entire career. Jensen’s work has focused on athletes with years of experience, which leads him to conclude that younger athletes may be more adaptable to making changes to their force curves. The point at which the fingerprint becomes harder to change “depends a lot on the rower’s individual body awareness and mental skill – and the coach of course.”

“I think the force curve can be changed,” says Jensen. “We can change it through rigging. But if the rower has been rowing for many years, it is very difficult to change them. Everyone can produce a perfect curve sub-maximally."

Although Jensen does feel there is an ideal curve, he suggests that different athlete force curves can actually work together optimally within the entire boat. “The important point,” he says, “is that in the crew boat the different profiles blend into an overall optimal boat profile. Coaches need to watch and determine how different athletes fit into each crew.”

When asked about using force curves to help in crew selection, Jensen says: “Yes, in theory, but I don’t think that we have enough evidence to make such decisions. From my experience, you don’t necessarily need to have the same curve. You can put a rower in with a beautiful curve, but he might still be an anchor.”

If young rowers were taught how to change their force curves on demand, then, would these athletes be more adaptable? More successful?

Casey Galvanek’s answer is yes. Galvanek, who coached the United Staters junior men’s eight to silver at the 2015 World Rowing Junior Championships in Rio, has over two decades of experience working with junior rowers.

“In the early 1990s I was trying to get kids to be carbon copies of one another,” says Galvanek. “I began to move away from that and had them be more natural and then rig the boats around them so that everything is happening at the same time with the right angles.”

Galvanek’s approach changed again in 2012 with the addition of a RowPerfect indoor rowing machine to his facilities. “I began looking at peak handle force,” he says. “Getting people to modify their application of power, how they open up during the drive, changing their hip drive and getting their curves to change.”

These athletes, says Galvanek, learn how to make the changes to their force curve in line with a crew standard. “Kids who have learned this way are definitely more flexible (to different coaching demands). They are more able to make the changes their coaches ask.”

Galvanek sees the ideal force curve as something particular to each crew. “Using the RowPerfect,” he explains, “I am able to say ‘ok, you need to change this a little bit to fit in with the crew.’ With big differences you have to change a bit of the rigging, but being able to have athletes modify how they apply their forces also means that you have to rig less.”

Both Galvanek and Jensen are quick to point out, however, that determination and attitude can make the difference at any age. “The kids who really want to make improvements,” says Galvanek, “will put in the practice and make the changes. The kids that don’t seem to care, they are just kind of doing it, they are the ones who don’t make changes.”

“Even a slight change can make a big difference,” concludes Jensen, “so you should not give up. It is a long process.”