Centrifugal acceleration to 3G_z is related to increased release of stress hormones and decreased mood in men and women

Figures & data

Table I.  ANOVA results for centrifuge vs. control.

PLASMA HORMONE	N (ce|co)	GROUP	MEASUREMENT	GROUP^*MEASUREMENT
Cortisol	11*10	F(1,19) = 5.71, p < 0.05*	F(2,38) = 10.64, p < 0.001***	F(2,38) = 14.22, p < 0.001***
Prolactin	11*10	F(1,19) = 7.55, p < 0.05*	F(2,38) = 3.12, p = 0.06	F(2.38) = 4.06, p < 0.05*
ACTH	10*6	F(1,14) = 3.95, p = 0.07	F(2,28) = 4.30, p < 0.05*	F(2,28) = 4.64, p < 0.05*
Epinephrine	11*11	F(1,20) = 2.45, p = 0.13	F(2,40) = 4.33, p < 0.05*	F(2,40) = 3.90, p < 0.05*
Norepinephrine	11*11	F(1,20) = .097, p = 0.76	F(2,40) = 2.36, p = 0.11	F(2,40) = 10.06, p < 0.001***

Note: ce- centrifuge group; co- control group.

Figure 1 Changes in plasma hormone concentrations for the centrifuge group who were exposed to 3G_z for 15 min and for the control group. Measurements were made before the centrifuge started (PRE) after it stopped (POST) and one hour later (POST 1HR). Measurements for the control group were chronologically comparable. Data show means ± 95% confidence intervals. Asterisks indicate significant changes compared with the previous measurement (PRE vs. POST vs. POST 1HR): *p < 0.05; **p < 0.01; ***p < 0.001.

Figure 2 Changes in perceived physical state (PEPS) (left) and the two EZ-scale dimensions motivational state (middle) and psychological strain (right) for measurements at time points PRE, POST and POST 1HR. Data show means, standard error (boxes) and standard deviation. Crosses indicate changes compared to POST: ^†p < 0.05.

Figure 3 Detailed view on the significant PEPS subdimension perceived physical health (left) and on the significant EZ-scale subdimensions calmness (second), readiness to strain (third) and self-confidence (right) during measurements PRE, POST and POST 1HR. Data show means, standard error (boxes) and standard deviation. Asterisks indicate significant differences from PRE measurements: *p < 0.05. Crosses indicate significant differences from POST measurement: ^††p < 0.01. Note that although self-confidence showed a significant effect in the ANOVA (Table II), post-hoc comparison showed no significant differences between the measurements.

Table II.  Friedmann's results and values for each of the three measurements for perceived physical state (PEPS) and the two EZ-scales psychological strain and motivational state and each of their subdimensions.

Group	PRE	POST	POST 1HR	ANOVA results (N = 11, FG = 2)
Perceived Physical State
Centrifuge	3.50 ∀ 1.55	3.03 ∀ 1.43	3.66 ∀ 0.85	χ^2 = 2.28, p = 0.32
Control	3.48 ∀ 0.74	3.32 ∀ 0.92	3.32 ∀ 0.69	χ^2 = 1.81, p = 0.40
Perceived physical energy
Centrifuge	3.69 ∀ 1.36	2.98 ∀ 1.25	3.39 ∀ 1.25	χ^2 = 3.35, p = 0.19
Control	3.73 ∀ 0.99	3.45 ∀ 1.19	3.39 ∀ 1.07	χ^2 = 3.15, p = 0.21
Perceived physical fitness
Centrifuge	3.14 ∀ 1.07	3.00 ∀ 1.52	3.57 ∀ 0.85	χ^2 = 3.32, p = 0.19
Control	3.27 ∀ 0.81	3.17 ∀ 0.91	3.16 ∀ 0.75	χ^2 = 0.40, p = 0.82
Perceived physical flexibility
Centrifuge	3.33 ∀ 1.18	2.97 ∀ 1.73	3.70 ∀ 0.77	χ^2 = 2.25, p = 0.32
Control	2.98 ∀ 0.96	2.86 ∀ 0.91	2.81 ∀ 0.69	χ^2 = 0.16, p = 0.92
Perceived physical health
Centrifuge*	3.86 ∀ 0.91	3.12 ∀ 1.69*	3.97 ∀ 0.80	χ^2 = 6.68, p < 0.05*
Control	3.93 ∀ 0.81	3.77 ∀ 1.02	3.93 ∀ 0.89	χ^2 = 1.87, p = 0.39
Perceived Psychological Strain
Centrifuge	3.38 ∀ 1.24	3.02 ∀ 1.49	3.67 ∀ 0.91	χ^2 = 4.90, p = 0.09
Control	3.69 ∀ 0.74	3.59 ∀ 0.65	3.62 ∀ 0.60	χ^2 = 0.15, p = 0.93
Calmness
Centrifuge*	3.36 ∀ 1.36	3.41 ∀ 1.76	4.22 ∀ 0.72*	χ^2 = 7.31, p < 0.05*
Control	3.91 ∀ 0.66	3.91 ∀ 0.74	3.95 ∀ 0.42	χ^2 = 0.31, p = 0.86
Positive mood
Centrifuge	3.77 ∀ 1.40	3.32 ∀ 1.62	3.50 ∀ 1.18	χ^2 = 2.55, p = 0.28
Control	4.00 ∀ 0.89	4.00 ∀ 0.89	3.95 ∀ 0.96	χ^2 = 0.00, p = 1.00
Recovery
Centrifuge	3.09 ∀ 1.56	2.32 ∀ 1.69	3.68 ∀ 1.21	χ^2 = 2.89, p = 0.24
Control	3.59 ∀ 1.14	3.32 ∀ 1.10	3.14 ∀ 1.31	χ^2 = 1.63, p = 0.44
Relaxation
Centrifuge	3.27 ∀ 1.57	3.05 ∀ 1.62	3.27 ∀ 1.10	χ^2 = 2.88, p = 0.24
Control	3.27 ∀ 0.96	3.14 ∀ 0.74	3.45 ∀ 0.69	χ^2 = 1.40, p = 0.50
Perceived Motivational State
Centrifuge*	3.10 ∀ 1.10	2.80 ∀ 1.27	3.42 ∀ 0.70^††	χ^2 = 7.32, p < 0.05*
Control	3.44 ∀ 0.58	3.40 ∀ 0.73	3.48 ∀ 0.63	χ^2 = 1.11, p = 0.57
Social acceptance
Centrifuge	3.00 ∀ 0.87	2.95 ∀ 1.01	3.27 ∀ 0.68	χ^2 = 3.89, p = 0.14
Control	3.73 ∀ 0.68	3.45 ∀ 0.76	3.68 ∀ 0.81	χ^2 = 4.45, p = 0.11
Willingness to seek contact
Centrifuge	3.32 ∀ 1.29	2.77 ∀ 1.51	3.27 ∀ 1.00	χ^2 = 4.42, p = 0.11
Control	3.73 ∀ 0.75	3.73 ∀ 0.90	3.77 ∀ 0.88	χ^2 = 0.33, p = 0.85
Self-confidence
Centrifuge*	3.00 ∀ 1.30	2.81 ∀ 1.35	3.50 ∀ 0.74	χ^2 = 6.06, p < 0.05*
Control	3.09 ∀ 0.38	3.27 ∀ 0.61	3.36 ∀ 0.64	χ^2 = 4.32, p = 0.12
Readiness to strain
Centrifuge**	3.09 ∀ 1.24	2.64 ∀ 1.47	3.64 ∀ 0.90^††	χ^2 = 10.76, p < 0.01**
Control	3.23 ∀ 0.90	3.14 ∀ 0.92	3.09 ∀ 0.86	χ^2 = 0.00, p = 1.00

Displayed are dimensions, PRE, POST, POST 1HR and Friedmann's ANOVA results below for each group (centrifuge and control). Values are means ± ( ∀ ) standard deviations (SD). Asterisks indicate significant difference when compared with PRE: *p < 0.05. Crosses indicate changes to measurement POST: ^††p < 0.01.