Generally, you cannot spot reduce fat. However, one study has shown some increased results in fat reduction around areas where muscles are contracted.

Aerobic exercise increases whole body adipose tissue lipolysis, but is lipolysis higher in subcutaneous adipose tissue (SCAT) adjacent to contracting muscles than in SCAT adjacent to resting muscles? Ten healthy, overnight-fasted males performed one-legged knee extension exercise at 25% of maximal workload (Wmax) for 30 min followed by exercise at 55% Wmax for 120 min with the other leg and finally exercised at 85% Wmax for 30 min with the first leg. Subjects rested for 30 min between exercise periods. Femoral SCAT blood flow was estimated from washout of 133Xe, and lipolysis was calculated from femoral SCAT interstitial and arterial glycerol concentrations and blood flow. In general, blood flow and lipolysis were higher in femoral SCAT adjacent to contracting than adjacent to resting muscle In conclusion, blood flow and lipolysis are generally higher in SCAT adjacent to contracting than adjacent to resting muscle irrespective of exercise intensity. Thus specific exercises can induce "spot lipolysis" in adipose tissue."
Time: 15-30 min






25%
Bloodflow
Wmax 6.6 ± 1.0 vs. 3.9 ± 0.8 ml·100 g–1·min–1
P < 0.05
25%
Lipolysis
Wmax 102 ± 19 vs. 55 ± 14 nmol·100 g–1·min–1
P = 0.06
55%
Bloodflow
Wmax 7.3 ± 0.6 vs. 5.0 ± 0.6 ml·100 g–1·min–1
P < 0.05
55%
Lipolysis
Wmax 86 ± 11 vs. 50 ± 20 nmol·100 g–1·min–1
P > 0.05
85%
Bloodflow
Wmax 6.6 ± 1.3 vs. 5.9 ± 0.7 ml·100 g–1·min–1,
P > 0.05
85%
Lipolysis
Wmax 88 ± 31 vs. –9 ± 25 nmol·100 g–1·min–1
P < 0.05

Am J Physiol Endocrinol Metab. 2007 Feb;292(2):E394-9. Epub 2006 Sep 19