One of the most common and moves in contra dance is the 'swing', where two people face each other, hold on in some fashion, and quickly spin clockwise. In modern urban contra every dance has a partner swing (doing the figure with the person you chose to dance with, every 30s or so), and maybe a bit more than half have a neighbor swing (doing the figure with a series of other people you meet in line).

The amount of force needed to hold two people together who are swinging quickly is pretty high. [1] I've written about some holds I think do a better job distributing the weight than the standard one, but after some discussion on the contracallers@ mailing list I was curious: what did people do historically?

I looked back at several older contra dance videos to see what holds people were using. What I'd call the "ballroom" swing was the most common, with outer hands (gent's left, lady's right) joined, gent's right hand behind lady's back, lady's left hand behind gent's shoulder. Another very common hold is what I'm calling a "forearm" hold, where the outer arms overlap more. In some videos nearly everyone is using one hold, while in others there's more variation.

1964, somewhere in New England:

A slightly shorter version of this video is also online by the videographer labeled 1967, and unfortunately I took the timestamps from that video. I see ballroom at 0:35, 0:37, 3:15, 3:16, 5:08, 5:10. At 1:05 (and then again in the background at 5:11, and then again at 5:23 and 5:33) I see a forearm hold with arms that are straighter than I'm used to. At 2:08 I see a hold where the gents hands are both around the lady's waist and the lady's hands are both over the tops of the gent's shoulders.

1976 in Bloomington IN:

Almost all the couples are swinging with a ballroom variation where the lady's left hand is on the back of the gent's right arm. One couple's doing a symmetrical swing with left hands joined low between their bodies.

1981 in Belmont MA:

This one is very long, and I only watched the contra portion from 9:17 to 13:00. Almost all the swings use a forearm hold, though I saw one couple doing that symmetrical swing at 10:52 and another doing a ballroom swing at 11:33.

1986 in Cambridge MA:

Outdoor demo performance. Almost all ballroom holds, but at 4:04 the couple all the way on the right has outer hands in a forearm hold (which they continue doing in later iterations of the dance). 1986 in Chico CA:

Almost all ballroom holds, except for one couple where the lady's left hand is on the back of the gent's right arm instead of behind his shoulder.

1986 in Francistown NH:

At 0:30 I see two ballroom holds and two forearm holds. At 1:06 I see two ballroom holds, one forearm hold, and one summetrical hold, though note that this is many of the same couples. Jumping ahead to 8:38 I see three forearm holds. Separately, I really like how enthusiastic the balances are: you can feel the room shake through to the camera!

1987 Mendocino CA:

I only see ballroom holds.

1989 Portland OR:

I see almost all ballroom. At 0:58 and then again at 1:28, 1:58, 3:02 etc there's a couple with the symmetrical hold. I didn't watch the whole video, so it's possible there were other couples that did other holds at some point?

1990 Cambridge MA:

I see forearm holds at 3:41 and 5:16. I see ballroom holds at 4:12, 4:14, 4:44, 5:17, 5:49, and 5:50. At 5:18 there's a ballroom variation where the lady's inner hand is behind the gent's arm. At 5:48 there's one where both lady's hands behind gent's shoulders, the gent's left hand is behind the lady's elbow, and the gent's right hand is behind lady's back.

[1] I tried to do some math on this, but the values are high enough that I don't tust it. If you like to spin quickly you might go 4.5x around in twelve beats, which is 45rpm at a tempo of 120bpm. Let's guess the people each weigh 150lb and approximate them as point masses one foot apart. Doing some math:

r = 1ft
m = 300lb
ω = 45rpm = 0.75 hz

v = ω2πr
  = 0.75 hz * 2π * 0.5ft
  = 4.7 ft/s

F = mv^2/r
  = 300lbm * (4.7 ft/s)^2 / 0.5ft
  = 300lbm * 11 ft / s^2
  = 3300lbm * ft / s^2

1lbf = 32.17 lbm * ft / s^2
1lbm = 0.0311 lbf * s^2 / ft

F = 3300 lbm * ft / s^2
  = 3300 * 0.0311 lbf
  = 103lbf

This says you need ~100lb of force to hold the dancers together! If you're spinning slower, perhaps 2.5x in twelve beats, it's still a significant 31lb.

https://www.jefftk.com/p/contra-avoiding-sore-arms