Online holiday spending outperformed offline spending in several key product categories according to comScore.

The top growing online product category for the season was sports & fitness, which grew 18 percent compared to a year ago. The category continues to benefit from consumers focus on health and fitness and consumers feeling more comfortable purchasing higher-price fit ness equipment, such as treadmills and elliptical machines, online.

The second fastest growing category was video games, consoles & accessories, which grew 14 percent on continued demand for popular consoles, such as the Nintendo Wii, Microsoft Xbox 360 and PlayStation 3.

Apparel & accessories, the only other product category with positive online growth, generated higher sales due to retailers heavy discounts and promotions, along with unfavorable weather across much of the country.

“For an online holiday shopping season that recorded a disappointing 3-percent decline in sales, a positive note is that e-commerce trends outperformed overall consumer spending in several product categories, which is to say that e-commerce continued to capture an increasing share of consumers’ wallet,” said comScore chairman Gian Fulgoni.

“Clearly, 2008 was an extremely challenging time for many retailers, and the beginning of 2009 may not be much better. But when the consumer economy eventually does rebound, e-commerce is poised to benefit from its emergence as an important consumer sales channel.”