Table 4.

Model accuracy, error and standard deviation.

	R2 adj	Original SD	GAM SD	Dev (%)	MAE	MAPE	RMSE	IOA	AIC
VO2max	0.42	5.19	3.36	0.43	3.07	0.07	3.92	0.77	12,650.32
Handgrip_strength	0.78	9.04	8	0.79	2.9	0.15	4.17	0.94	12,917.68
Vertical_jump	0.6	6.85	5.28	0.6	3.35	0.16	4.32	0.86	13,080.14
Fat_mass	0.78	6.85	6.05	0.78	2.35	0.12	3.18	0.94	11,719.91
Muscle_mass	0.78	6.46	5.68	0.78	2.24	0.03	3.03	0.93	11,500.14
MFR	0.42	0.63	0.41	0.43	0.24	0.01	0.48	0.76	3157.65
HBMI	0.74	0.4	0.34	0.74	0.15	0.15	0.2	0.92	− 722.76

R2 adj Adjusted R2, Original SD Standard deviation of the original variable, GAM SD Model standard deviation, Dev (%) Deviance explained, MAE Mean Absolute Error, MAPE Mean Absolute Percentage Error, RMSE Root Mean Square Error, IOA Index of Agreement, AIC Akaike Information Criterion, VO₂max maximal oxygen uptake, MFR muscle-fat-ratio, HBMI handgrip strength to body mass index.