Jump in if you’re ready for a hike

LAP pools are for swimmers, but what’s a walker to do to stay cool when working out? Pool equipment makers are coming up with powerful jets and underwater treadmill-like devices to lure walkers into the water.

Gorilla jets, three to four times stronger than normal spa jets, shoot hundreds of gallons of water a minute into a pool or spa, generating a fast, strong current that is hard to walk into.

Just ask Karen Bradford. When she moved into her new Placentia home, she wanted a pool for entertainment and exercise. So she had California Pools & Spa design and build a “spool,” an oversized spa (8 feet wide by 15 feet long) with a faux rock waterfall to lounge under.

Installed on one end, however, are four super-powered swim jets that each pump out 250 gallons of water per minute. Her grown sons have to fight the jets to walk forward in the 3 1/2 -foot-deep water while her husband stands against the jets for a pummeling back massage.

Usually in a spa, all jets share one pump, but in this spool, there is a pump for every two jets, which supplies more pressure and allows more water to be moved, says designer Quinton Steimle of California Pools ([626] 974-9417; www.californiapools.com). The currents will be stronger in a smaller pool. The additional cost of the 2-inch-wide jets and installation in a new pool is about $5,000, he says.

Nonmotorized as well as motorized treadmill-like devices -- once used only in physical rehabilitative programs -- are being dropped into pools deeper than 4 feet and used as part of a resistance-exercise routine. Compact, noncorrosive frames with walking belts that can be added to existing pools start at $1,900 and are sold by several companies. SwimEx Inc. ([800] 877-7946; www.swimex.com) makes one that can be adjusted to increase the resistance.

-- Janet Eastman