The effects of cigarette smoking on aerobic and anaerobic capacity and heart rate variability among female university students

Figures & data

Table 1 Physiological characteristics of the participants

Variables	Smoker (n=12)	Nonsmoker (n=21)
Age (years)	20.6 ± 1.4	20.4 ± 0.5
Height (cm)	163.4 ± 5.5	160.1 ± 4.5
Weight (kg)	63.7 ± 9.4	53.9 ± 5.5
Body mass index (kg/m^2)	24.0 ± 3.7	21.2 ± 2.6
Smoking history in cigarettes per month	46.8 ± 20.0	None
Self-determined morbidity and medical history	None	None

Note: Values are presented as mean ± standard deviations.

Abbreviation: n, number.

Figure 1 Schematic of the 6 × 10-second intermittent sprint test.

Notes: The ◎ symbol represents the measurement of oxygen saturation levels. ⬇: Blood lactate evaluation.

: Blood pressure measurement (includes baseline, postexercise, and recovery).

Figure 2 The participants’ anaerobic performance and fatigue index during the 6 × 10-second IST.

Notes: *Time by condition interaction (P<0.05); ^#differed significantly according to condition; and the values shown are mean ± standard deviations. (A) The participants’ performance regarding the IST was denoted by total work, (B) peak power, (C) average power, and (D) fatigue index.
Abbreviation: IST, an intermittent sprint test.

Figure 3 Rating of perceived exertion for smoking and nonsmoking groups during the intermittent sprint test.

Note: *Time by condition interaction (P<0.05).

Table 2 Blood pressure at various time points for the participants in the smoking and nonsmoking groups

	Smoking (n=12)		Nonsmoking (n=21)
	Systolic pressure (mmHg)	Diastolic pressure (mmHg)	Systolic pressure (mmHg)	Diastolic pressure (mmHg)
Baseline	107.7 ± 8.7	69.9 ± 8.4	116.9 ± 19.1	71.4 ± 7.5
Postexercise	130.5 ± 15.1*,#	76.6 ± 10.8*,#	125.0 ± 12.7*,#	76.5 ± 9.2*,#
Recovery	97.9 ± 28.4	63.8 ± 7.3	108.6 ± 10.8	69.6 ± 7.5

Notes: Values are presented as mean ± standard deviations.

* Significantly different from baseline (P<0.01)

# significantly different from recovery (P<0.05).

Abbreviation: n, number.

Figure 4 Time-domain analysis of heart rate variability at rest and after the 6 × 10-second intermittent sprint test for the participants in the smoking and nonsmoking groups.

Notes: (A) R–R interval; (B) SDNN; (C) RMSSD; and (D) pNN50. The values shown are mean ± standard deviations. *Time by condition interaction (P<0.01).
Abbreviations: Pre-Ex, preexercise; Post-Ex, postexercise; SDNN, standard deviation of the normal to normal interval; RMSDD, root mean square successive difference; pNN50, percentage of adjacent normal R–R intervals >50 ms.

Figure 5 Frequency-domain analysis of heart rate variability at rest and after the 6 × 10-second intermittent sprint test for the participants in the smoking and nonsmoking groups.

Notes: (A) lnLF; (B) lnHF; (C) lnLF/lnHF; (D) LF/HF; (E) LFnu; and (F) HFnu. The values shown are the mean ± standard deviations. *The time by condition interaction (P<0.01); ^#the significant main effect between the smoking and nonsmoking groups (P<0.05).
Abbreviations: lnLF, natural logarithm of low frequency; Pre-Ex, preexercise; Post-Ex, postexercise; lnHF, natural logarithm of high frequency; lnLF/lnHF, natural logarithm of low/high frequency; LF/HF, low frequency/high frequency ratio; LFnu, normalized LF; HFnu, normalized HF.