Saw a tinman elite vid the other day where the guy was trying to "strengthen his plantar". So there's a 3rd way!
*Nobody has a "plantar" or a "plantars". Plantar is a location, like dorsal or ventral. Its just fascia, its a connective tissue on the plantar aspect of your foot. Just like a plantar wart is not a "plantar's wart" and/or unique in any way. Its a wart, just on the plantar aspect of your foot. You can no more strengthen your fascia than you can strengthen your acl. A tendon is different.