Table 2.

Effects of exercise training on human blood levels of leptin.

Citation	n, gender	Group	Exercise program	Diet restriction	Duration of intervention	Preleptin (ng/mL)	Postleptin (ng/mL)	P value	Changes of body mass (BM), body mass index (BMI), fat mass (FM), and % body fat mass (% BFM)
Aerobic exercise
Houmard et al. [35]	7 m, 9 f	Younger lean	Cycle ergometer at 70–75% $\dot{\text{V}}$O2 max for 60 min	None	7 days	7.1 ± 1.3	7.6 ± 1.3	NS	BM: NS
	6 m, 8 f	Older subjects with relatively more adipose tissue	Same as above	None	7 days	14.2 ± 2.7	11.0 ± 1.3	NS	BM: NS
Halle et al. [36]	20 m	Obese with T2DM	Cycle ergometer for 30 min on 5 times/week at 70% HRM (1,100 kcal/wk)	Diet consisted of a 1,000-kcal diabetic diet with a carbohydrate content of ~50%, a fat content of 25%, and a protein content of 25%	4 weeks	7.9 ± 4.4	5.6 ± 3.5	P < 0.001	BMI: decrease
Ishii et al. [37]	9 m, 14 f	T2DM exercise training with diet therapy	Walking and cycle ergometer exercise at 50% of $\dot{\text{V}}$O2 max for 60 min on at least 5 times/week	25- to 27-kcal/kg/day diet (54% to 58% carbohydrate, 22% to 24% protein, 18% to 20% fat)	6 weeks	7.2 ± 3.6	4.6 ± 2.5	P < 0.05	BM, BMI, and % BFM: NS
	11 m, 16 f	T2DM diet therapy alone	None	Same as above	6 weeks	6.9 ± 3.4	5.6 ± 2.9	NS	BM, BMI, and % BFM: NS
Boudou et al. [38]	8 m	T2DM control	None	None	8 weeks	7.26 ± 3.85	7.40 ± 3.95	NS	BM and BMI: NS; Visceral and subcutaneous adipose tissue (cm2): NS
	8 m	T2DM exercise	Endurance exercise (75% VO2 peak, 45 min) twice a week, with intermittent exercise (five 2 min exercises at 85% VO2 peak separated by 3 min exercises at 50% VO2 peak) once a week, on a cycle ergometer	None	8 weeks	6.05 ± 4.60	5.60 ± 4.30	NS	BM and BMI: NS; Visceral and subcutaneous adipose tissue (cm2): decrease
Kraemer et al. [39]	14 f	Overweight control	None	None	9 weeks	33.24 ± 3.78	34.69 ± 3.14	NS	BM, BMI, and % BFM: NS
	16 f	Overweight exercise	Three-four times/week of four 20–30 min/session. Two of the exercise days consisted of step aerobics and 1-2 of the exercise days consisted of treadmill or stationary cycle exercise	None	9 weeks	28.0 ± 2.13	31.04 ± 2.71	NS	BM, BMI, and % BFM: NS
Hickey et al. [40]	9 m	Middle aged sedentary	Exercise training consists of overground and/or treadmill walking and/or running for 45 min on 4 times/week at 85% HRM	None	12 weeks			NS	BM, FM, and % FM: NS
	9 f	Middle aged sedentary	Same as above	None	12 weeks		Decrease of 17.5%	P < 0.05	BM, FM, and % FM: NS
Ozcelik et al. [41]	14 f	Obese	Cycle ergometer for approximately 45 min on 3-4 times/week. Training exercise intensity was established using the anaerobic threshold.	None	12 weeks	23.62 ± 3.5	13.13 ± 3.4	P = 0.0001	BM, BMI, and FM: decrease
Polak et al. [42]	25 f	Obese premenopausal	Aerobic exercise (aerobic exercise performed in gymnasium and cycleergometer) for 45 min on 5 times/week at 50% $\dot{\text{V}}$O2 max	None	12 weeks	24.3 ± 8.7	18.1 ± 8.3	P < 0.001	BM, BMI, and % BFM: decrease
Okazaki et al. [43]	15 f	Obese	Cycle ergometer or indoor walking for 30 min and low-impact aerobics for 30 min at 50% $\dot{\text{V}}$O2 max	Mild hypocalbolic diet	12 weeks	14.7 ± 5.3	8.9 ± 3.6	P < 0.001	BM, BMI, and FM: decrease
	26 f	Nonobese	Same as above	Same as above	12 week	7.6 ± 3.9	5.6 ± 2.2	P < 0.01	BM, BMI, and FM: decrease
Pérusse et al. [44]	51 m	Sedentary adult	The subjects worked on cycle ergometer at an intensity corresponding to 55% of $\dot{\text{V}}$O2 max for 30 min per session at the beginning, increasing progressively toward an intensity of 75% of $\dot{\text{V}}$O2 max for 50 min during the last 6 weeks of the training protocol.	None	20 weeks	4.6 ± 4.4	3.9 ± 4.2	P = 0.004	BMI: NS; FM and % BFM: decrease
	46 f		Same as above	None	20 weeks	11.9 ± 8.5	12.4 ± 8.1	NS	BMI, FM, and % BMF: NS
Kondo et al. [45]	8 f	Nonobese control	None	None	7 months	6.7 ± 1.2	6.5 ± 2.2	NS	BM, BMI: NS; FM and % BFM: decrease
	8 f	Obese	Exercise training (fast slope walking, slope jogging, dumbbells, stretching, leg cycling, and jumping rope) for 30–60 min at 60–70% HRR on 4-5 times/week	None	7 months	16.4 ± 4.6	12.3 ± 5.4	P < 0.05	BM, BMI, FM, and % BFM: decrease
Reseland et al. [46]	37 m	MS control	None	None	1 year	12.0 ± 10.1	0.5 ± 4.6 (Change)	NS	BMI, FM, and % BFM: NS
	44 m	MS diet	None	Dietary counseling	1 year	8.7 ± 4.3	−0.7 ± 3.0	P < 0.05	BMI, FM, and % BFM: decrease
	48 m	MS exercise	Endurance exercise (aerobics, circuit training, and fast walking) and jogging for 60 min on 3 times/week	None	1 year	9.8 ± 4.9	−0.4 ± 2.3	NS	BMI: NS; FM and % BFM: decrease
	57 m	MS diet + exercise	Same as above	Dietary counseling	1 year	9.1 ± 6.2	−2.2 ± 2.4	P < 0.001	BMI, FM, and % BFM: decrease
Miyatake et al. [47]	36 m	Overweight	Aerobic exercise (walking, aerobic dance, and swimming) and resistance training (leg extension and leg flexion) for 90 min at 50–65% HRM	None	1 year	6.7 ± 4.0	5.1 ± 3.1	P < 0.01	BM, BMI, FM, and % BFM: decrease
Hsieh and Wang [48]	22 m, 30 f	Younger T2DM	Endurance exercise for 20 min at 50–74% HRM	Subjects were prescribed a diet with 500 kcal/day deficit.	1 year	17.62 ± 3.18	14.00 ± 3.16	P = 0.03	BMI, and % BFM: decrease
	20 m, 30 f	Older T2DM	Same as above	Same as above	1 year	17.81 ± 2.15	12.63 ± 2.09	P = 0.02	BMI, and % BFM: decrease
Resistance exercise
Ryan et al. [49]	8 f	Nonobese postmenopausal women RT	Three exercise sessions/week on pneumatic variable resistance machines	None	16 weeks	14.6 ± 3.3	14.8 ± 3.0	NS	BM, BMI, FM, and % BFM: NS
	7 f	Obese postmenopausal women RT + WL	Same as above	Dietary counseling and energy restriction (hypocaloric diets)	16 weeks	22.9 ± 3.9	14.6 ± 2.6	P < 0.01	BM, BMI, FM, and % BFM: decrease
Fatouros et al. [50]	10 m	Overweight elderly control	None	None	24 weeks	9.5 ± 0.8	9.4 ± 0.7	NS	BM and BMI: NS
	14 m	Overweight elderly low-intensity RT	RT for approximately 60 min on 3 times/week at 45–50% of 1RM	None	24 weeks	9.1 ± 0.7	8.8 ± 0.7	P < 0.05	BM: NS; BMI: decrease
	12 m	Overweight elderly moderate- intensity RT	RT for approximately 60 min on 3 times/week at 60–65% of 1RM	None	24 weeks	8.9 ± 0.6	8.7 ± 0.4	P < 0.05	BM: NS; BMI: decrease
	14 m	Overweight elderly high- intensity RT	RT for approximately 60 min on 3 times/week at 80–85% of 1RM	None	24 weeks	9.7 ± 0.6	7.8 ± 0.6	P < 0.05	BM: NS; BMI: decrease

Results are reported as mean ± SD or SE; P value reported for pre- versus postvalues. f: female; HRM: heart rate maximum; m: male; NS: not significant; RM: repetition maximum; RT: resistance training; T2DM: type 2 diabetes; $\dot{\text{V}}$O₂ max: maximal oxygen uptake; WL: weight loss.