▁full ▁mus cle ▁fi ber ▁rec ruit ment ▁the ▁speed ▁of ▁the ▁lift ▁must ▁be ▁prop uls ive ▁through ▁the ▁entire ▁range ▁of ▁the ▁movement ▁up ▁until ▁release . ▁▁ 3 . ▁Int ens ity ▁of ▁the ▁exercise . ▁The ▁duration ▁of ▁the ▁lift ▁should ▁be ▁measured ▁by ▁repet itions ▁or ▁time . ▁The ▁lift ▁should ▁be ▁stopped ▁when ▁the ▁bar ▁dec eler ates . ▁Research ▁has ▁shown ▁the ▁ 6 - 8 ▁repet itions ▁or ▁ 2 0 – 3 0 ▁seconds ▁produces ▁the ▁best ▁results . ▁▁ 4 . ▁Card i ov asc ular ▁benefits . ▁Ball istic ▁exer cis es ▁performed ▁continu ously ▁for ▁a ▁minimum ▁of ▁ 2 0 ▁seconds ▁followed ▁by ▁a ▁ 3 0 - second ▁rest ▁period ▁and ▁then ▁repeated ▁until ▁dec eler ation ▁occurs ▁has ▁been ▁proven ▁to ▁elev ate ▁the ▁heart ▁rate ▁to ▁training ▁zone ▁level . ▁▁▁ 5 . ▁Co - ord ination . ▁Research ▁at ▁the ▁University ▁of ▁Connecticut ▁found ▁that ▁high - int ens ity ▁training ▁has ▁prof ound ▁effects ▁on ▁the ▁nerv ous ▁system . ▁The ▁exercise ▁had ▁to ▁be ▁of ▁an ▁intensity ▁that ▁elev ate ▁the ▁heart ▁rate ▁to ▁ 9 0 % ▁of ▁maximum ▁rate ▁and ▁had ▁to ▁sust ain ▁that ▁rate ▁for ▁at ▁least ▁ 2 0 ▁seconds . ▁▁ 6 . ▁Electron ic ▁measurement . ▁There ▁are ▁several ▁electronic ▁measurement ▁systems ▁that ▁measure ▁the ▁velocity , ▁power , ▁and ▁effect iveness ▁of ▁a ▁lift . ▁The ▁ath lete ▁should ▁stop ▁the ▁lift ▁when ▁the ▁speed ▁of