Immersed in Momentum

I have had opportunities to meet up with some coaches during my trip to England. Some of our conversations have involved questions about ‘momentum’.

One of them asked if I could write up some notes that he could use. I have set up a Google Doc to do this and drafted a short summary for him. It is a partial bibliography.

I did not go back to primary sources such as Ivan PavlovEdward Thorndike, and Burrhus Frederic Skinner. My search started in the 1970s with Tony Nevin and extended to Walid Briki and Keith Markman’s (2018) paper on the phenomenology of goal pursuit.

The review gave me the opportunity to reflect on coaching applications of psychological momentum and behavioural momentum ideas notwithstanding the existential dilemma about whether ‘momentum’ exists or whether it can be defined.

A number of sport specific papers helped me focus my attention for my coaching friends:

Peter Adler and Patricia Adler (1978), The role of momentum in sport

Seppo Iso-Ahola and Ken Mobily (1980), Psychological momentum: A phenomenon and an empirical (unobtrusive) validation of its influence in a competitive sport tournament

Charles Mace, Joseph Lalli, Michael Shea, and John Nevin (1992), Behavioral momentum in college basketball

Jim Taylor and Andrew Demick (1994), A multidimensional model of momentum in sports

Judith Smith (2000), Psychological momentum in elite athletes

Alistair Higham, Chris Harwood, and Andrew Cale (2005), Momentum in soccer: Controlling the game

Lee Crust and Mark Nesti (2006), A review of psychological momentum in sports: Why qualitative research is needed

Martin Jones and Chris Harwood (2008), Psychological momentum within competitive soccer: Players’ perspectives

Joseph Wanzek, Daniel Houlihan, and Kendra Homan (2012), An Examination of Behavioral Momentum in Girl’s High School Volleyball

Walid Briki et al. (2012), A qualitative exploration of the psychological contents and dynamics of momentum in sport.

Philip Mortimer and Edward Burt (2014), Does momentum exist in elite handball?

Carsten Larsen and Kristoffer Henriksen (2015), Psychological momentum in team sport: An intervention program in professional soccer

Rafael Barragán (2015), Quantitative and qualitative analysis of the critical moments in basketball

Seppo Iso-Ahola and Charles Dotson (2017), Momentum and elite performance

Walid Briki (2017), Rethinking the relationship between momentum and sport performance: toward an integrative perspective

There are numerous other papers with a sport specific focus. I will need to return to some of these but have become acquainted with them through the meta-analysis in the papers listed here.

I did pursue the psychology literature too and was delighted to learn more about: momentum as a metaphor; discriminated operants; resistance; behavioural dynamics; reinforcement; compliance; naive beliefs; triggers; amplification; perception; and incentives.

I was keen to find papers my coaching colleagues could read and I decided I would recommend Philip Mortimer and Edward Burt’s (2014), Does momentum exist in elite handball? and Carsten Larsen and Kristoffer Henriksen’s (2015), Psychological momentum in team sport: An intervention program in professional soccer.

Philip and Edward share some excellent visualisations of momentum shifts in game state (that reminded me of other conversations with coaches about T-patterns). Carsten and Kristoffer shared an example of working with young football players “to increase the players’ awareness of triggers, of cognitive, affective, and behavioral changes associated with PM, and of how players may control perceptions of PM during training and in matches”. I thought this example from Denmark resonated with work shared by Alistair Higham, Chris Harwood, and Andrew Cale (2005), Lee Crust and Mark Nesti (2006), and Martin Jones and Chris Harwood (2008). I felt very comfortable with the qualitative tenor of this work and thought coaches would be very comfortable in 1:1 conversations with players.

Amidst all this reading and reflection, I was delighted to find Walid Briki and Keith Markman’s (2018) discussion of prospection and the situation of pre-experience in training environments and simulations. This speaks to my fascination with [simple_tooltip content=’Peter Dowrick’]feedforward[/simple_tooltip] and my growing interest in consequences in training contexts. It gave me a new reference: Daniel Gilbert and Timothy Wilson (2007) and their exploration of the mechanisms of prospection:

Mental simulation is the means by which the brain discovers what it already knows. When faced with decisions about future events, the cortex generates simulations, briefly tricking subcortical systems into believing that those events are unfolding in the present and then taking note of the feelings these systems produce.

Which seems to me to be the start of a whole lot of new conversations about learning design and guided discovery with coaches.

Photo Credits

[simple_tooltip content=’Chosen from the free photos on Unsplash’]Photo[/simple_tooltip] of person throwing white fish net on body of water by David Clode on  Unsplash
Rugby photo by Quino Al on Unsplash

Random walks and momentum shifts in the 2018 Super Netball Grand Final


The Sunshine Coast Lightning defeated West Coast Fever in the 2018 Super Netball Grand Final.

Prior to the game, I had identified some performance bandwidth profiles for both teams. Post-game, the performance profiles of both teams were:

Sunshine Coast

The team’s actual performance delivered an exceptional third quarter and moved the team into a game-winning position.

West Coast

The scoring sequence in the game was:

Random Walks

In 2006, Martin Lames explored dynamic interactions in sport games. His discussion included an examination of handball possession in terms of interlaced random walks and the momentary strength of competing teams.

Martin conjectures in his paper:

There is evidence for the hypothesis that a team’s scoring rate is independent from the one of other team, but we see also phases with a seemingly strong dependence. Moreover, sometimes the momentary scoring probabilities seem to be negatively correlated (my team is good when the other is bad and vice versa), but sometimes there is a positive relationship (my team performs well when the other does so).

There have been subsequent discussions of random walk in the literature. See, for example: Alan Gabel and Sidney Redner (2012); Leto Peel and Aaron Clauset (2015); Dilan Kiley et al (2016); and Jaime Prieto, Miguel-Angel Gomez and Jaime Sampaio (2016).

In their discussion, Alan and Sidney noted:

There are three factors that determine which team scores. First, the better team has a greater intrinsic chance of scoring. The second factor is the anti- persistence of successive scoring events that arises from the change of possession after a score. The last is the linear restoring force, in which the scoring probability of a team decreases as its lead increases (and vice versa for a team in deficit).

Leto and Aaron propose:

Anti-restoration or momentum occurs when the leading team has a higher chance of scoring again.

Momentum is the reverse of restoration.

Dilan and his colleagues note:

Each game generates a probabilistic, rule-based story, and the stories of games provide a range of motifs which map onto narratives found across the human experience: dominant, one-sided performances; back-and-forth struggles; underdog upsets; and improbable comebacks.

The Final

I used secondary day from Champion Data’s record of the Final. I though I would look for random walks and momentum changes in the data.

I used RStudio, ggplot2, and ggrepel to visualise the data. My record of the game tracks the Sunshine Coast’s score difference performance. Green shaded areas indicate Sunshine Coast lead. The second quarter is in purple to indicate West Coast’s lead throughout that quarter.

The data show eight excellent examples of the tendency of a random walk to move to a central location. Each of them exists at a new equilibrium in the game.

I have included some time-in-game labels to indicate my perception of a momentum shift. The ability for a team to create these episodes (and respond to them when opponents are driving the game) resonates powerfully with some of the discussions about temporal (T) patterns and their critical interval relationships initiated by Magnus Magnusson.

It would be fascinating to learn how coaches from both teams addressed these shifts in the messages they shared with their players. It would be interesting to learn what was said at half time too. The half time break straddled a seven-goal run from the Sunshine Coast.


I have really enjoyed this season’s Super Netball competition. The final was closely contested. I was particularly interested in the pivot in the game that occurred in the third quarter. The Sunshine Coast produced their best third quarter of their entire season. Their previous highest score in the third quarter was 18. West Coast had experience of teams lifting in the third quarter in recent games. Their opponents in weeks 13 and 14 of the regular season had both scored 20 goals.

My pre-game priors suggested that West Coast would win the Final by 3 goals. At 13 minutes and 05 seconds in the second quarter West Coast led by 7 goals. What happened thereafter provides a case study of the interlacing of random walks in the context of momentum shifts … for an away team.

Photo Credits

Super Netball (Sue Gaudron Q & A)

Lightning (Twitter)

Performance after a Bye Week in the Regular AFL 2017 Season

Each team had a bye week in the regular AFL 2017 season.

My visualisation of the momentum of the teams from their Bye Week is:

The same chart with a legend:

The extremes of these momentum lines are Sydney and North Melbourne:

My rank order for momentum after a Bye Week is:


One of my interests in doing this work is to imagine the kind of conversations that might be occurring in performance departments during the post-bye period.